diff --git a/README.md b/README.md
index 68db26b48..3d5918681 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,4 @@
-What is CoG?
-============
+# What is CoG?
 
 CoG is a multi-institutional project that seeks to examine, within the Earth sciences, 
 the organizational characteristics of community software projects and to create software infrastructure 
@@ -12,24 +11,25 @@ and that exposing those characteristics and linking them is a way to make a comp
 The CoG project created the CoG environment - this website - as a way of promoting good governance across numerous projects 
 and organizations in the Earth system sciences.  Its structure encourages information sharing among projects, transparency and trust.
 
-For more information, visit: http://earthsystemcog.org/
+For more information, visit: http://esgf.github.io/COG
 
-Manual CoG update
------------------
+## Recent Updates
 
-```
-cd /usr/local/cog/cog_install
-git fetch
-git checkout v3.15.4 # or master, devel, etc.
-/etc/cog-wsgi-8889/apachectl restart  # for ESGF > v4.0.0 
-# previous versions restart node: esg-node restart 
-```
+### v4.0.3
 
-Latest release: v3.15.4
------------------------
+* Drop processing of use of next=url in add user query string.
 
- - Add link to clear data cart to appear on pages that import the "middle navbar"
+### v4.0.2
+* Bug fix for Show Citation (missing data from API causes all information not to display)
 
-Previous updates
+## Python3 Update
+
+This is v4.0.3 of CoG that supports Python3 and Django 2.2.24.  Given that this Django 2.2 version has run in LLNL production for over eight months now, it is time that we release this version of COG as the master branch.  We strongly encourage all sites to upgrade their deployments to this version.
+
+The last v3.x version of CoG running with Python2 is preserved for legacy.  This version is still needed to create the cogdb database (see below) for a standard legacy ESGF deployment using the Ansible playbooks (although a Postgres >9.5 supported version may be forthcoming....).
+
+## Updating CoG
+
+Use the Ansible playbook from the following branch: `python3_cog` - See https://esgf.github.io/esgf-ansible for instructions on how to run the playbooks. 
+The installation must be performed on a server that already has the cogdb deployed to PostgreSQL.  In other words, in order to install CoG v4 from scratch, you must first run the latest Ansible playbook for ESGF, which will deploy CoG v3.15 (Python2) and create the cogdb database.  Then, run the  `python3_cog` branch playbook to setup CoG.  Note that this installation will create a distinct Python3 conda environment for which to run the CoG service in mod_wsgi_express `py3_cog`.  The previous `cog` environment will still be present, but is no longer used (and could be safely deleted).
 
- - Updates to templates for help information in preparation for the retirement of the CU CoG site.
diff --git a/apache/wsgi.py b/apache/wsgi.py
index 27733709c..c1afd57fe 100644
--- a/apache/wsgi.py
+++ b/apache/wsgi.py
@@ -28,18 +28,18 @@
 os.environ.setdefault("DJANGO_SETTINGS_MODULE", "settings")
 
 # print debugging information
-print 'Using Python version: %s' % sys.version
-print 'Using Python path: %s' % sys.path
-print 'PYTHONPATH=%s' % os.environ.get('PYTHONPATH', None)
-print 'LD_LIBRARY_PATH=%s' % os.environ.get('LD_LIBRARY_PATH', None)
-print 'SSL_CERT_DIR=%s' % os.environ.get('SSL_CERT_DIR', None)
-print 'SSL_CERT_FILE=%s' % os.environ.get('SSL_CERT_FILE', None)
+print('Using Python version: %s' % sys.version)
+print('Using Python path: %s' % sys.path)
+print('PYTHONPATH=%s' % os.environ.get('PYTHONPATH', None))
+print('LD_LIBRARY_PATH=%s' % os.environ.get('LD_LIBRARY_PATH', None))
+print('SSL_CERT_DIR=%s' % os.environ.get('SSL_CERT_DIR', None))
+print('SSL_CERT_FILE=%s' % os.environ.get('SSL_CERT_FILE', None))
 
 try:
     application = get_wsgi_application()
-    print 'WSGI without exception'
+    print('WSGI without exception')
 except Exception:
-    print 'handling WSGI exception'
+    print('handling WSGI exception')
     # Error loading applications
     if 'mod_wsgi' in sys.modules:
         traceback.print_exc()
diff --git a/cog/config/search/__init__.py b/cog/config/search/__init__.py
index 3c1e72fc5..a088cfd2e 100644
--- a/cog/config/search/__init__.py
+++ b/cog/config/search/__init__.py
@@ -1 +1 @@
-from config_project_search import SearchConfigParser
\ No newline at end of file
+from .config_project_search import SearchConfigParser
\ No newline at end of file
diff --git a/cog/config/search/config_project_search.py b/cog/config/search/config_project_search.py
index 4a3592eb2..386402e2f 100644
--- a/cog/config/search/config_project_search.py
+++ b/cog/config/search/config_project_search.py
@@ -1,4 +1,4 @@
-import sys, os, ConfigParser
+import sys, os, configparser
 from django.conf import settings
 from cog.models import Project, SearchGroup, SearchFacet
 from cog.utils import str2bool
@@ -15,7 +15,7 @@ def __init__(self, project):
     def _getConfigParser(self):
         
         # read project configuration
-        configParser = ConfigParser.RawConfigParser()
+        configParser = configparser.RawConfigParser()
         # must set following line explicitly to preserve the case of configuration keys
         configParser.optionxform = str 
         
@@ -25,7 +25,7 @@ def _getConfigParser(self):
     def write(self):
         '''Writes the project search configuration to the file $COG_CONFIG_DIR/projects/<project_short_name>/search.cfg'''
         
-        print 'Writing search configuration for project=%s' % self.project.short_name
+        print('Writing search configuration for project=%s' % self.project.short_name)
         
         # load project search profile
         project = Project.objects.get(short_name=self.project.short_name)
@@ -66,7 +66,7 @@ def write(self):
     def read(self):
         '''Reads the project search configuration from the file $COG_CONFIG_DIR/projects/<project_short_name>/search.cfg'''
         
-        print 'Reading search configuration for project=%s' % self.project.short_name
+        print('Reading search configuration for project=%s' % self.project.short_name)
         
         # load project search profile
         project = Project.objects.get(short_name=self.project.short_name)
@@ -74,7 +74,7 @@ def read(self):
         
         # remove existing groups of facets
         for group in search_profile.groups.all():
-            print 'Deleting search group=%s' % group
+            print('Deleting search group=%s' % group)
             group.delete()
         
         # read project configuration
@@ -82,7 +82,7 @@ def read(self):
         try:
             projConfig.read( self.config_file_path )
         except Exception as e:
-            print "Configuration file %s not found" % self.config_file_path
+            print("Configuration file %s not found" % self.config_file_path)
             raise e
         
         # loop over configuration sections
@@ -110,7 +110,7 @@ def read(self):
         
                 for option in projConfig.options(section):
                     value = projConfig.get(section, option)
-                    print section, option, value
+                    print(section, option, value)
                     parts = value.split("|")
                     facet_order = int(option)
                     facet_key = parts[0]
diff --git a/cog/db_migrations/django_openid_auth/0001_initial.py b/cog/db_migrations/django_openid_auth/0001_initial.py
index 8a4aba821..24f3d5068 100644
--- a/cog/db_migrations/django_openid_auth/0001_initial.py
+++ b/cog/db_migrations/django_openid_auth/0001_initial.py
@@ -39,7 +39,7 @@ class Migration(migrations.Migration):
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('claimed_id', models.TextField(unique=True, max_length=2047)),
                 ('display_id', models.TextField(max_length=2047)),
-                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL)),
+                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
     ]
diff --git a/cog/forms/__init__.py b/cog/forms/__init__.py
index 463f90a06..686b091bc 100644
--- a/cog/forms/__init__.py
+++ b/cog/forms/__init__.py
@@ -1,10 +1,10 @@
-from forms_image import *
-from forms_account import *
-from forms_bookmarks import *
-from forms_governance import *
-from forms_others import *
-from forms_post import *
-from forms_project import *
-from forms_aboutus import *
-from forms_search import *
-from forms_access_control import *
\ No newline at end of file
+from .forms_image import *
+from .forms_account import *
+from .forms_bookmarks import *
+from .forms_governance import *
+from .forms_others import *
+from .forms_post import *
+from .forms_project import *
+from .forms_aboutus import *
+from .forms_search import *
+from .forms_access_control import *
\ No newline at end of file
diff --git a/cog/forms/forms_account.py b/cog/forms/forms_account.py
index e10b7c78e..458fa239d 100644
--- a/cog/forms/forms_account.py
+++ b/cog/forms/forms_account.py
@@ -286,7 +286,7 @@ def validate_username(form, user_id):
                         
                         # once the openid is validated, choose the closest possible username
                         _username = createUsername(username)
-                        print 'Created username=%s from=%s' % (_username, username)
+                        print('Created username=%s from=%s' % (_username, username))
                         cleaned_data['username'] = _username  # override form data
             else:
                 # django will automatically check that the username is unique in the CoG database
@@ -304,6 +304,6 @@ def validate_field(form, field_name, field_value):
 def validate_ascii(form, field_name, field_value):
     if field_value:
         try:
-            field_value.decode('ascii')
+            field_value.encode('ascii')
         except (UnicodeDecodeError, UnicodeEncodeError):
             form._errors[field_name] = form.error_class(["'%s' contains invalid characters." % field_name])
\ No newline at end of file
diff --git a/cog/forms/forms_image.py b/cog/forms/forms_image.py
index 2fc471e63..aedd1e2e1 100644
--- a/cog/forms/forms_image.py
+++ b/cog/forms/forms_image.py
@@ -23,6 +23,6 @@ def clean(self):
                 self._errors["image"] = self.error_class(["Image size exceeds the maximum allowed."])
         except OSError as e:
             # image not existing on disk
-            print e
+            print(e)
         
         return self.cleaned_data
\ No newline at end of file
diff --git a/cog/forms/forms_others.py b/cog/forms/forms_others.py
index 9069155cd..037e20ba7 100644
--- a/cog/forms/forms_others.py
+++ b/cog/forms/forms_others.py
@@ -126,10 +126,10 @@ def clean(self):
                        
             file_ext = str(os.path.splitext(thefile.name)[1])
             mime_type = magic.from_buffer(thefile.read(1024), mime=True)
-            print "Validating file extension=%s, mime type=%s" % (file_ext, mime_type)
+            print("Validating file extension=%s, mime type=%s" % (file_ext, mime_type))
             if not file_ext:
                 self._errors["file"] = self.error_class(["File name must have an extension."])
-            elif file_ext.lower() not in VALID_MIME_TYPES.keys():
+            elif file_ext.lower() not in list(VALID_MIME_TYPES.keys()):
                 self._errors["file"] = self.error_class(["File extension %s is not supported." % file_ext])
             elif mime_type not in VALID_MIME_TYPES[file_ext.lower()]:
                 self._errors["file"] = self.error_class(["File extension %s does not match its valid mime type." %
diff --git a/cog/forms/forms_post.py b/cog/forms/forms_post.py
index dc746213f..e2a5906b1 100644
--- a/cog/forms/forms_post.py
+++ b/cog/forms/forms_post.py
@@ -137,7 +137,7 @@ def clean(self):
         # validate "topic"
         # cannot set both 'topic' and 'newtopic'
         if topic and newtopic:
-            errmsg = u"Please either choose an existing topic OR create a new one"
+            errmsg = "Please either choose an existing topic OR create a new one"
             self._errors["topic"] = self.error_class([errmsg])
             del cleaned_data["topic"]
             del cleaned_data["newtopic"]
@@ -152,6 +152,13 @@ def clean(self):
 
             cleaned_data["topic"] = topic
 
+        # check if the 'label' field is set for hyperlink and page posts
+        # if 'label' is blank, then fill the field with the first 28 characters of 'title'        
+        if type == Post.TYPE_PAGE or type == Post.TYPE_HYPERLINK:
+            label = cleaned_data["label"]
+            if label is None:
+                cleaned_data["label"] = cleaned_data["title"][:28]
+
         # prevent XSS on fields 'title', 'label', 'newtopic'
         for key in ["title", "label", "newtopic"]:
             if key in cleaned_data:
diff --git a/cog/forms/forms_project.py b/cog/forms/forms_project.py
index aae51da08..1c5b1b4d0 100644
--- a/cog/forms/forms_project.py
+++ b/cog/forms/forms_project.py
@@ -19,10 +19,10 @@ class ProjectForm(ModelForm):
     # define the widget for parent/peer selection so we can set the styling. The class is set to .selectfilter and its
     # styles are controlled in cogstyle.css
 
-    parents = forms.ModelMultipleChoiceField("parents", required=False,
+    parents = forms.ModelMultipleChoiceField(queryset=Project.objects.all(), required=False,
                                              widget=forms.SelectMultiple(attrs={'size': '20',
                                                                                 'class': 'selectprojects'}))
-    peers = forms.ModelMultipleChoiceField("peers", required=False,
+    peers = forms.ModelMultipleChoiceField(queryset=Project.objects.all(), required=False,
                                            widget=forms.SelectMultiple(attrs={'size': '20',
                                                                               'class': 'selectprojects'}))
     # filtering of what is see in the form is done down below. 
@@ -99,7 +99,7 @@ def clean_long_name(self):
         
         # check for non-ascii characters
         try:
-            long_name.decode('ascii')
+            long_name.encode('ascii')
         except (UnicodeDecodeError, UnicodeEncodeError):
             raise forms.ValidationError("Project long name contains invalid non-ASCII characters")
         return long_name
@@ -156,7 +156,7 @@ def clean(self):
         features = self.cleaned_data.get('software_features')
         if not hasText(features):
             self._errors["software_features"] = self.error_class(["'SoftwareFeatures' must not be empty."])
-            print 'error'
+            print('error')
         return self.cleaned_data
 
 
@@ -174,7 +174,7 @@ class ProjectTagForm(ModelForm):
     # form constructor in views_project.py
 
     # field['tags'] is the list of preexisting tags
-    tags = forms.ModelMultipleChoiceField("tags", required=False,
+    tags = forms.ModelMultipleChoiceField(queryset=Project.objects.all(), required=False,
                                           widget=forms.SelectMultiple(attrs={'size': '7'}))
 
     # override __init__ method to change the queryset for 'tags'
diff --git a/cog/forms/forms_search.py b/cog/forms/forms_search.py
index d3df7082e..80265a7c2 100644
--- a/cog/forms/forms_search.py
+++ b/cog/forms/forms_search.py
@@ -15,7 +15,12 @@ def clean_url(self):
         return clean_url_field(self, 'url')
     
     def clean_constraints(self):
-        return clean_url_field(self, 'constraints')
+        # if no constraints are found, then return an empty string
+        data = self.cleaned_data['constraints']
+        if data is None:
+            return ''
+        else:
+            return clean_url_field(self, 'constraints')
 
 
 class SearchFacetForm(ModelForm):
diff --git a/cog/forms/forms_utils.py b/cog/forms/forms_utils.py
index bba31ce3e..9e8ceedde 100644
--- a/cog/forms/forms_utils.py
+++ b/cog/forms/forms_utils.py
@@ -26,7 +26,7 @@ def validate_image(form, field_name):
         # validate image header
         try:
             image_type = imghdr.what(image)
-            print 'Validating image header: detected image type=%s' % image_type
+            print('Validating image header: detected image type=%s' % image_type)
             if image_type is None:
                 form._errors[field_name] = form.error_class(["Invalid image type: %s" % image_type])
         except Exception as e:
diff --git a/cog/installation/config.py b/cog/installation/config.py
index 0413b6319..489a4e2da 100644
--- a/cog/installation/config.py
+++ b/cog/installation/config.py
@@ -23,15 +23,15 @@
 
 '''
 
-import ConfigParser
-import StringIO
+import configparser
+import io
 import collections
 import logging
 import os
 import time
 from django.utils.crypto import get_random_string
 
-from constants import (SECTION_DEFAULT, COG_SECTION_DEFAULT, SECTION_ESGF, SECTION_EMAIL,
+from .constants import (SECTION_DEFAULT, COG_SECTION_DEFAULT, SECTION_ESGF, SECTION_EMAIL,
                        ESGF_PROPERTIES_FILE, ESGF_PASSWORD_FILE,
                        IDP_WHITELIST, KNOWN_PROVIDERS, PEER_NODES,
                        DEFAULT_PROJECT_SHORT_NAME)
@@ -59,7 +59,7 @@ def _readCogConfig(self):
         '''Method that reads an existing COG configuration file, or create a new one if not existing.'''
 
         # initialize COG configuration file
-        self.cogConfig = ConfigParser.ConfigParser(allow_no_value=True,
+        self.cogConfig = configparser.ConfigParser(allow_no_value=True, 
                                                    dict_type=collections.OrderedDict)
         # must set following line explicitly to preserve the case of configuration keys
         self.cogConfig.optionxform = str
@@ -79,7 +79,7 @@ def _readCogConfig(self):
                 logging.info("Configuration file: %s not found, will create new one" % CONFIGFILEPATH )
 
         except Exception as e:
-            print e
+            print(e)
             logging.error("Error reading configuration file: %s" % CONFIGFILEPATH)
             logging.error(e)
 
@@ -88,7 +88,7 @@ def _readEsgfConfig(self):
         '''Method that reads local parameters from ESGF configuration file esgf.properties.'''
 
         # read ESGF configuration file ($esg_config_dir/esgf.properties), if available
-        self.esgfConfig = ConfigParser.ConfigParser()
+        self.esgfConfig = configparser.ConfigParser()
         try:
             self.esgfConfig.read(ESGF_PROPERTIES_FILE)
         except IOError:
@@ -103,7 +103,7 @@ def _readEsgfConfig(self):
                 with open(ESGF_PROPERTIES_FILE, 'r') as f:
                     # transform Java properties file into python configuration file: must prepend a section
                     config_string = '[%s]\n' % SECTION_DEFAULT + f.read()
-                    config_file = StringIO.StringIO(config_string)
+                    config_file = io.StringIO(config_string)
                     self.esgfConfig.readfp(config_file)
                 logging.info("Read ESGF configuration parameters from file: %s" % ESGF_PROPERTIES_FILE)
 
@@ -168,7 +168,7 @@ def _setupConfig(self):
         # default search service URL, before any project customization
         self._safeSet('DEFAULT_SEARCH_URL','http://%s/esg-search/search/' % hostName)
         # interval between updates of user's projects, during user session
-        self._safeSet('MY_PROJECTS_REFRESH_SECONDS', 3600)
+        self._safeSet('MY_PROJECTS_REFRESH_SECONDS', '3600')
         # optional number of days after which password expire
         self._safeSet('PWD_EXPIRATION_DAYS','0')
         # optional top-level URL to redirect user registration (no trailing '/')
@@ -188,13 +188,13 @@ def _setupConfig(self):
         # PEER_NODES = /esg/config/esgf_cogs.xml
         self._safeSet('PEER_NODES', PEER_NODES)
         # option to send SESSION and CSRF cookies via SSL only - requires full SSL-encrypted site
-        self._safeSet('PRODUCTION_SERVER', True)
+        self._safeSet('PRODUCTION_SERVER', 'True')
         # ESGF software stack version
         esgfVersion = self._safeGet("version", default=None)
         if esgfVersion:
             self._safeSet('ESGF_VERSION', esgfVersion, override=True)
         # option to disable CAPTCHA for creating account in automatic testing
-        self._safeSet('USE_CAPTCHA', True)
+        self._safeSet('USE_CAPTCHA', 'True')
 
 
         #[ESGF]
diff --git a/cog/installation/install.py b/cog/installation/install.py
index 0fef6e910..c9e64c1bb 100644
--- a/cog/installation/install.py
+++ b/cog/installation/install.py
@@ -168,7 +168,7 @@ def _createObjects(self):
             except ObjectDoesNotExist:
                 site = Site.objects.create(name=idpHostname, domain=idpHostname)
                 idpPeerSite = PeerSite.objects.create(site=site, enabled=True)
-            print '\tCreated IdP Peer site: %s with enabled=%s' % (idpPeerSite, idpPeerSite.enabled)
+            print('\tCreated IdP Peer site: %s with enabled=%s' % (idpPeerSite, idpPeerSite.enabled))
 
             
     def _getRootAdminPassword(self):
diff --git a/cog/installation/setup.py b/cog/installation/setup.py
index f7ca458f3..e1951ea65 100644
--- a/cog/installation/setup.py
+++ b/cog/installation/setup.py
@@ -25,25 +25,25 @@ def finalize_options(self):
     def run(self):
         
         # 1) create/update cog_settings.cfg BEFORE Django is started
-        print '>>> 1) Executing CogConfig...'
-        from config import CogConfig
+        print('>>> 1) Executing CogConfig...')
+        from .config import CogConfig
         cogConfig = CogConfig(self.esgf)
         cogConfig.config()
-        print '<<< ...done with CogConfig'
+        print('<<< ...done with CogConfig')
         
         # 2) setup Django registry to initialize CoG application
-        print '>>> 2) Setting up Django applications registry'
+        print('>>> 2) Setting up Django applications registry')
         os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'
         import django
         django.setup()
-        print '<<< ... done with django.setup()'
+        print('<<< ... done with django.setup()')
              
         # 3) use cog_settings.cfg to install/upgrade CoG database
-        print '>>> 3) Executing CoGInstall...'
-        from install import CoGInstall
+        print('>>> 3) Executing CoGInstall...')
+        from .install import CoGInstall
         cogInstall = CoGInstall()
         cogInstall.install()
-        print '<<< ...done with CoGInstall'
+        print('<<< ...done with CoGInstall')
     
     
 if __name__ == '__main__':
diff --git a/cog/management/commands/init_site.py b/cog/management/commands/init_site.py
index 3b7c3d8ef..5bfea44cc 100644
--- a/cog/management/commands/init_site.py
+++ b/cog/management/commands/init_site.py
@@ -20,4 +20,4 @@ def handle(self, *ags, **options):
         current_site.domain = settings.SITE_DOMAIN
         current_site.save()
 
-        print 'Updated current site: name=%s domain=%s' % (current_site.name, current_site.domain)
\ No newline at end of file
+        print('Updated current site: name=%s domain=%s' % (current_site.name, current_site.domain))
\ No newline at end of file
diff --git a/cog/management/commands/sync_projects.py b/cog/management/commands/sync_projects.py
index 712277565..8261f79c9 100644
--- a/cog/management/commands/sync_projects.py
+++ b/cog/management/commands/sync_projects.py
@@ -15,4 +15,4 @@ class Command(BaseCommand):
     def handle(self, *ags, **options):
         
         sites = projectManager.sync()
-        print 'sync_projects: time=%s synchronized projects from sites=%s' % (datetime.datetime.now(), sites)
\ No newline at end of file
+        print('sync_projects: time=%s synchronized projects from sites=%s' % (datetime.datetime.now(), sites))
\ No newline at end of file
diff --git a/cog/management/commands/sync_sites.py b/cog/management/commands/sync_sites.py
index d21b1a336..7aa8d3649 100644
--- a/cog/management/commands/sync_sites.py
+++ b/cog/management/commands/sync_sites.py
@@ -36,5 +36,6 @@ def handle(self, *args, **options):
         try:
             pnl = PeerNodesList(FILEPATH)
             pnl.reload(delete=options['delete'])
-        except Exception, error:
-            print "Could not update peer nodes from xml file", error
+        except Exception as error:
+            print("Could not update peer nodes from xml file")
+            print(error)
diff --git a/cog/management/commands/sync_users.py b/cog/management/commands/sync_users.py
index 269e717d5..7886dec54 100644
--- a/cog/management/commands/sync_users.py
+++ b/cog/management/commands/sync_users.py
@@ -7,7 +7,7 @@
 from django.core.management.base import BaseCommand
 from django.contrib.auth.models import User
 from cog.models.user_profile import isUserLocal
-import urllib
+import urllib.request, urllib.parse, urllib.error
 
 HTTP_STATUS_CODE_OK = 200
 HTTP_STATUS_CODE_NOT_FOUND = 404
@@ -24,21 +24,21 @@ def handle(self, *ags, **options):
                 
                 # test user existence by accessing the profile page
                 userProfileUrl = user.profile.getAbsoluteUrl()
-                print "\nChecking user at URL: %s" % userProfileUrl.decode("utf-8")
+                print("\nChecking user at URL: %s" % userProfileUrl)
                 
                 try:
-                    response = urllib.urlopen( userProfileUrl )
+                    response = urllib.request.urlopen( userProfileUrl )
                     if response.getcode()==HTTP_STATUS_CODE_NOT_FOUND:
                         
-                        print '\tUser not found on remote node %s, deleting from local database...' % user.profile.site.domain
+                        print('\tUser not found on remote node %s, deleting from local database...' % user.profile.site.domain)
                         # delete this user from local database
                         user.delete()
                     else:
-                        print '\tUser found.'
+                        print('\tUser found.')
                          
                 # error checking this user
                 except Exception as exception:
-                    print 'Error checking URL: %s skipping... ' % userProfileUrl
-                    print exception
+                    print('Error checking URL: %s skipping... ' % userProfileUrl)
+                    print(exception)
                     pass
                     
\ No newline at end of file
diff --git a/cog/middleware/init_middleware.py b/cog/middleware/init_middleware.py
index 4ea9a819d..c4ec2240e 100644
--- a/cog/middleware/init_middleware.py
+++ b/cog/middleware/init_middleware.py
@@ -8,30 +8,36 @@
 
 class InitMiddleware(object):
 
-    def __init__(self):
-
-        print 'Executing CoG initialization tasks'
-
+    def __init__(self, get_response):
+        self.get_response = get_response
+        
+        print('Executing CoG initialization tasks')
+        
         # update name, domain of current site into database
         current_site = Site.objects.get_current()
         current_site.name = settings.SITE_NAME
         current_site.domain = settings.SITE_DOMAIN
         current_site.save()
-        print 'Updated current site: name=%s domain=%s' % (current_site.name, current_site.domain)
-
+        print('Updated current site: name=%s domain=%s' % (current_site.name, current_site.domain))
+        
         # update list of ESGF peers into database
         filepath = siteManager.get('PEER_NODES')
         try:
             pnl = PeerNodesList(filepath)
             pnl.reload() # delete=False
-        except Exception, error:
-            print "Could not update peer nodes from xml file", error
+        except Exception as error:
+            print("Could not update peer nodes from xml file")
+            print(error)
 
         # read IdP whitelist
 
         # remove this class from the middleware that is invoked for every request
         raise MiddlewareNotUsed('Do not invoke ever again')
 
+    def __call__(self, request):
+        response = self.get_response(request)
+        return response
+
     def process_request(self, request):
-        print 'This line should never be printed...'
+        print('This line should never be printed...')
         return None
diff --git a/cog/middleware/login_middleware.py b/cog/middleware/login_middleware.py
index 407a80b76..0fe2d105c 100644
--- a/cog/middleware/login_middleware.py
+++ b/cog/middleware/login_middleware.py
@@ -6,16 +6,17 @@
 '''
 
 from django.http import HttpResponseRedirect
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.conf import settings
 from cog.plugins.esgf.registry import LocalWhiteList
 
 class LoginMiddleware(object):
 
-    def __init__(self):
+    def __init__(self, get_response):
 
-        
         try:
+            self.get_response = get_response
+
             # initialize the white list service
             self.whitelist = LocalWhiteList(settings.IDP_WHITELIST)
                 
@@ -32,6 +33,10 @@ def __init__(self):
             # OSError: [Errno 2] No such file or directory: '/esg/config/esgf_idp_static.xml'
             self.init = False
 
+    def __call__(self, request):
+        response = self.get_response(request)
+        return response
+
     def process_request(self, request):
         '''
         Method called before processing of the view.
@@ -78,17 +83,17 @@ def process_response(self, request, response):
             # process errors from openid authentication
             if request.path == self.url2:
     
-                if request.method=='POST' and not request.user.is_authenticated():
+                if request.method=='POST' and not request.user.is_authenticated:
                     if response.status_code == 500:
-                        print 'Authentication Error'
-                        print response
+                        print('Authentication Error')
+                        print(response)
                         if 'OpenID discovery error' in response.content:
                             return HttpResponseRedirect(reverse('openid-login')+"?message=openid_discovery_error&next=%s&openid=%s" % (next, openid_identifier) )
     
             # process errors from standard authentication
             elif request.path == self.url1:
     
-                if request.method=='POST' and not request.user.is_authenticated():
+                if request.method=='POST' and not request.user.is_authenticated:
                     return HttpResponseRedirect(reverse('login')+"?message=login_failed&next=%s&username=%s" % (next, username) )
 
         return response
diff --git a/cog/middleware/password_middleware.py b/cog/middleware/password_middleware.py
index 01865c82a..0fbfa909f 100644
--- a/cog/middleware/password_middleware.py
+++ b/cog/middleware/password_middleware.py
@@ -3,7 +3,7 @@
 '''
 
 from django.http import HttpResponseRedirect
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.core.exceptions import ObjectDoesNotExist
 
 EXEMPT_URLS = ['/password/update/', 'site_media', 'logout']
@@ -18,8 +18,8 @@ def process_request(self, request):
         
         if not any(url in request.path for url in EXEMPT_URLS):
             try:
-                if request.user.is_authenticated() and request.user.profile.type==1 and request.user.profile.hasPasswordExpired():
-                    print 'Password for user %s has expired, forcing mandatory change.' % request.user
+                if request.user.is_authenticated and request.user.profile.type==1 and request.user.profile.hasPasswordExpired():
+                    print('Password for user %s has expired, forcing mandatory change.' % request.user)
                     return HttpResponseRedirect(reverse('password_update', kwargs={'user_id':request.user.id})+"?message=password_expired&next=%s" % request.path)
                 
             except ObjectDoesNotExist:
diff --git a/cog/middleware/session_middleware.py b/cog/middleware/session_middleware.py
index 0f24a9701..a16d99258 100644
--- a/cog/middleware/session_middleware.py
+++ b/cog/middleware/session_middleware.py
@@ -11,6 +11,13 @@
 
 class SessionMiddleware(object):
     
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        response = self.get_response(request)
+        return response
+
     def process_request(self, request):
         '''
         Method called before processing of the view.
@@ -19,7 +26,7 @@ def process_request(self, request):
         
         # must not use shared anonymous session
         try:
-            if request.user.is_authenticated() and request.user.profile.openid() is not None:
+            if request.user.is_authenticated and request.user.profile.openid() is not None:
             
                 s = request.session
                 last_accessed_seconds = s.get('LAST_ACCESSED', 0) # defaults to Unix Epoch
diff --git a/cog/migrations/0001_initial.py b/cog/migrations/0001_initial.py
index 038e8dc77..5604a2765 100644
--- a/cog/migrations/0001_initial.py
+++ b/cog/migrations/0001_initial.py
@@ -54,15 +54,15 @@ class Migration(migrations.Migration):
             name='CommunicationMeansMember',
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
-                ('communicationMeans', models.ForeignKey(to='cog.CommunicationMeans')),
-                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL)),
+                ('communicationMeans', models.ForeignKey(to='cog.CommunicationMeans', on_delete=models.CASCADE)),
+                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
             name='DataCart',
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
-                ('user', models.OneToOneField(related_name='datacart', to=settings.AUTH_USER_MODEL)),
+                ('user', models.OneToOneField(related_name='datacart', to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -71,7 +71,7 @@ class Migration(migrations.Migration):
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('identifier', models.CharField(max_length=200)),
                 ('date', models.DateTimeField(auto_now_add=True, verbose_name=b'Date Time')),
-                ('cart', models.ForeignKey(related_name='items', to='cog.DataCart')),
+                ('cart', models.ForeignKey(related_name='items', to='cog.DataCart', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -79,7 +79,7 @@ class Migration(migrations.Migration):
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('key', models.CharField(max_length=200)),
-                ('item', models.ForeignKey(related_name='keys', to='cog.DataCartItem')),
+                ('item', models.ForeignKey(related_name='keys', to='cog.DataCartItem', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -87,7 +87,7 @@ class Migration(migrations.Migration):
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('value', models.CharField(max_length=1000, null=True, blank=True)),
-                ('key', models.ForeignKey(related_name='values', to='cog.DataCartItemMetadataKey')),
+                ('key', models.ForeignKey(related_name='values', to='cog.DataCartItemMetadataKey', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -121,7 +121,7 @@ class Migration(migrations.Migration):
                 ('name', models.CharField(max_length=200)),
                 ('active', models.BooleanField(default=True)),
                 ('order', models.IntegerField(default=0, blank=True)),
-                ('parent', models.ForeignKey(related_name='parent_folder', blank=True, to='cog.Folder', null=True)),
+                ('parent', models.ForeignKey(related_name='parent_folder', blank=True, to='cog.Folder', null=True, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -151,7 +151,7 @@ class Migration(migrations.Migration):
                 ('is_private', models.BooleanField(default=False, verbose_name=b'Private?')),
                 ('order', models.IntegerField(default=0, blank=True)),
                 ('author', models.ForeignKey(related_name='forum_topics', on_delete=django.db.models.deletion.SET_NULL, verbose_name=b'Author', to=settings.AUTH_USER_MODEL, null=True)),
-                ('forum', models.ForeignKey(related_name='topics', to='cog.Forum')),
+                ('forum', models.ForeignKey(related_name='topics', to='cog.Forum', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -170,7 +170,7 @@ class Migration(migrations.Migration):
                 ('object_type', models.CharField(max_length=100, verbose_name=b'Object Type')),
                 ('object_id', models.IntegerField(verbose_name=b'Object Identifier')),
                 ('timestamp', models.DateTimeField(auto_now=True, verbose_name=b'Last Update Date')),
-                ('owner', models.ForeignKey(verbose_name=b'Owner', to=settings.AUTH_USER_MODEL)),
+                ('owner', models.ForeignKey(verbose_name=b'Owner', to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -199,8 +199,8 @@ class Migration(migrations.Migration):
             name='ManagementBodyMember',
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
-                ('managementBody', models.ForeignKey(to='cog.ManagementBody')),
-                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL)),
+                ('managementBody', models.ForeignKey(to='cog.ManagementBody', on_delete=models.CASCADE)),
+                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -217,8 +217,8 @@ class Migration(migrations.Migration):
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('date', models.DateTimeField(auto_now=True, verbose_name=b'Request Date')),
-                ('group', models.ForeignKey(to='auth.Group')),
-                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL)),
+                ('group', models.ForeignKey(to='auth.Group', on_delete=models.CASCADE)),
+                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -255,8 +255,8 @@ class Migration(migrations.Migration):
             name='OrganizationalRoleMember',
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
-                ('organizationalRole', models.ForeignKey(to='cog.OrganizationalRole')),
-                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL)),
+                ('organizationalRole', models.ForeignKey(to='cog.OrganizationalRole', on_delete=models.CASCADE)),
+                ('user', models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -264,7 +264,7 @@ class Migration(migrations.Migration):
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('enabled', models.BooleanField(default=False)),
-                ('site', models.OneToOneField(related_name='peersite', to='sites.Site')),
+                ('site', models.OneToOneField(related_name='peersite', to='sites.Site', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -327,7 +327,7 @@ class Migration(migrations.Migration):
                 ('author', models.ForeignKey(on_delete=django.db.models.deletion.SET_NULL, default=None, blank=True, to=settings.AUTH_USER_MODEL, null=True)),
                 ('parents', models.ManyToManyField(related_name='parent_projects', to='cog.Project', blank=True)),
                 ('peers', models.ManyToManyField(related_name='peer_projects', to='cog.Project', blank=True)),
-                ('site', models.ForeignKey(default=1, to='sites.Site')),
+                ('site', models.ForeignKey(default=1, to='sites.Site', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -337,7 +337,7 @@ class Migration(migrations.Migration):
                 ('title', models.CharField(default=b'', help_text=b'Title for this impact.', max_length=200)),
                 ('description', models.TextField(help_text=b'Describe a major impact of this project in its field.', verbose_name=b'Project Impact')),
                 ('order', models.IntegerField(blank=True)),
-                ('project', models.ForeignKey(related_name='impacts', to='cog.Project')),
+                ('project', models.ForeignKey(related_name='impacts', to='cog.Project', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -347,8 +347,8 @@ class Migration(migrations.Migration):
                 ('url', models.CharField(default=b'', unique=True, max_length=200, verbose_name=b'URL', blank=True)),
                 ('label', models.CharField(max_length=40)),
                 ('active', models.BooleanField(default=True)),
-                ('parent', models.ForeignKey(blank=True, to='cog.ProjectTab', null=True)),
-                ('project', models.ForeignKey(related_name='tabs', to='cog.Project')),
+                ('parent', models.ForeignKey(blank=True, to='cog.ProjectTab', null=True, on_delete=models.CASCADE)),
+                ('project', models.ForeignKey(related_name='tabs', to='cog.Project', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -363,7 +363,7 @@ class Migration(migrations.Migration):
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('order', models.IntegerField(default=0)),
-                ('project', models.ForeignKey(to='cog.Project')),
+                ('project', models.ForeignKey(to='cog.Project', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -394,7 +394,7 @@ class Migration(migrations.Migration):
                 ('latestSearchFlag', models.BooleanField(default=False)),
                 ('localSearchFlag', models.BooleanField(default=False)),
                 ('description', models.TextField(help_text=b'Optional description of this project search capabilities.', null=True, verbose_name=b'Search Help', blank=True)),
-                ('project', models.OneToOneField(to='cog.Project')),
+                ('project', models.OneToOneField(to='cog.Project', on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -421,9 +421,9 @@ class Migration(migrations.Migration):
                 ('researchKeywords', models.CharField(default=b'', max_length=60, null=True, blank=True)),
                 ('type', models.IntegerField(default=1)),
                 ('last_password_update', models.DateTimeField(null=True, verbose_name=b'Date and Time when Password was Last Updated', blank=True)),
-                ('site', models.ForeignKey(default=1, to='sites.Site')),
+                ('site', models.ForeignKey(default=1, to='sites.Site', on_delete=models.CASCADE)),
                 ('tags', models.ManyToManyField(related_name='users', to='cog.ProjectTag', blank=True)),
-                ('user', models.OneToOneField(related_name='profile', to=settings.AUTH_USER_MODEL)),
+                ('user', models.OneToOneField(related_name='profile', to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE)),
             ],
         ),
         migrations.CreateModel(
@@ -432,23 +432,23 @@ class Migration(migrations.Migration):
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                 ('url', models.URLField(max_length=1000, verbose_name=b'URL')),
                 ('name', models.CharField(max_length=200)),
-                ('profile', models.ForeignKey(to='cog.UserProfile')),
+                ('profile', models.ForeignKey(to='cog.UserProfile', on_delete=models.CASCADE)),
             ],
         ),
         migrations.AddField(
             model_name='searchgroup',
             name='profile',
-            field=models.ForeignKey(related_name='groups', to='cog.SearchProfile'),
+            field=models.ForeignKey(related_name='groups', to='cog.SearchProfile', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='searchfacet',
             name='group',
-            field=models.ForeignKey(related_name='facets', to='cog.SearchGroup', null=True),
+            field=models.ForeignKey(related_name='facets', to='cog.SearchGroup', null=True, on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='projecttopic',
             name='topic',
-            field=models.ForeignKey(to='cog.Topic'),
+            field=models.ForeignKey(to='cog.Topic', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='project',
@@ -463,7 +463,7 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='post',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='post',
@@ -473,12 +473,12 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='organizationalrole',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='organization',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='news',
@@ -488,12 +488,12 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='news',
             name='project',
-            field=models.ForeignKey(verbose_name=b'About Project', to='cog.Project'),
+            field=models.ForeignKey(verbose_name=b'About Project', to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='managementbody',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='managementbody',
@@ -503,57 +503,57 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='loggedevent',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='loggedevent',
             name='user',
-            field=models.ForeignKey(to=settings.AUTH_USER_MODEL),
+            field=models.ForeignKey(to=settings.AUTH_USER_MODEL, on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='fundingsource',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='forumthread',
             name='topic',
-            field=models.ForeignKey(related_name='threads', to='cog.ForumTopic'),
+            field=models.ForeignKey(related_name='threads', to='cog.ForumTopic', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='forum',
             name='project',
-            field=models.OneToOneField(related_name='forum', to='cog.Project'),
+            field=models.OneToOneField(related_name='forum', to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='folder',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='externalurl',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='doc',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='communicationmeans',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='collaborator',
             name='project',
-            field=models.ForeignKey(to='cog.Project'),
+            field=models.ForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='bookmark',
             name='folder',
-            field=models.ForeignKey(to='cog.Folder'),
+            field=models.ForeignKey(to='cog.Folder', on_delete=models.CASCADE),
         ),
         migrations.AddField(
             model_name='bookmark',
diff --git a/cog/migrations/0002_auto_20150706_1045.py b/cog/migrations/0002_auto_20150706_1045.py
index 2b5dc67a3..5a2732500 100644
--- a/cog/migrations/0002_auto_20150706_1045.py
+++ b/cog/migrations/0002_auto_20150706_1045.py
@@ -15,11 +15,11 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='folder',
             name='project',
-            field=cog.models.dbutils.UnsavedForeignKey(to='cog.Project'),
+            field=cog.models.dbutils.UnsavedForeignKey(to='cog.Project', on_delete=models.CASCADE),
         ),
         migrations.AlterField(
             model_name='projecttab',
             name='project',
-            field=cog.models.dbutils.UnsavedForeignKey(related_name='tabs', to='cog.Project'),
+            field=cog.models.dbutils.UnsavedForeignKey(related_name='tabs', to='cog.Project', on_delete=models.CASCADE),
         ),
     ]
diff --git a/cog/models/__init__.py b/cog/models/__init__.py
index e16ef3fda..b69e39e20 100644
--- a/cog/models/__init__.py
+++ b/cog/models/__init__.py
@@ -1,59 +1,59 @@
 # Users, Groups
-from user_profile import UserProfile, isUserValid, isUserLocal, isUserRemote, discoverSiteForUser, getDataCartsForUser, isOpenidLocal
-from user_url import UserUrl
-from membership import MembershipRequest
-from collaborator import Collaborator
+from .user_profile import UserProfile, isUserValid, isUserLocal, isUserRemote, discoverSiteForUser, getDataCartsForUser, isOpenidLocal
+from .user_url import UserUrl
+from .membership import MembershipRequest
+from .collaborator import Collaborator
 
 # Data Cart
-from datacart import DataCart, DataCartItem, DataCartItemMetadataKey, DataCartItemMetadataValue
+from .datacart import DataCart, DataCartItem, DataCartItemMetadataKey, DataCartItemMetadataValue
 
 # Projects
-from topic import Topic
-from project import *
-from project_topic import ProjectTopic
-from project_tab import *
-from news import News
-from project_tag import ProjectTag, MAX_PROJECT_TAG_LENGTH
-from project_impact import ProjectImpact
+from .topic import Topic
+from .project import *
+from .project_topic import ProjectTopic
+from .project_tab import *
+from .news import News
+from .project_tag import ProjectTag, MAX_PROJECT_TAG_LENGTH
+from .project_impact import ProjectImpact
 
 # Peers
-from peer_site import PeerSite, getPeerSites
+from .peer_site import PeerSite, getPeerSites
 
 # Posts
-from doc import Doc
-from post import Post
-from external_url import ExternalUrl
+from .doc import Doc
+from .post import Post
+from .external_url import ExternalUrl
 
 # Bookmarks
-from folder import Folder, getTopFolder, getTopSubFolders, TOP_FOLDER, TOP_SUB_FOLDERS
-from bookmark import Bookmark
+from .folder import Folder, getTopFolder, getTopSubFolders, TOP_FOLDER, TOP_SUB_FOLDERS
+from .bookmark import Bookmark
 
 # Search
-from search_profile import SearchProfile
-from search_group import SearchGroup
-from search_facet import SearchFacet
+from .search_profile import SearchProfile
+from .search_group import SearchGroup
+from .search_facet import SearchFacet
 
 # Governance
-from funding_source import FundingSource
-from organization import Organization
-from management_body import ManagementBody, getManagementBodies, ManagementBodyPurpose, initManagementBodyPurpose
-from management_body_member import ManagementBodyMember
-from communication_means import CommunicationMeans
-from communication_means_member import CommunicationMeansMember
-from organizational_role import OrganizationalRole, getLeadOrganizationalRoles, getMemberOrganizationalRoles, getOrganizationalRoles
-from organizational_role_member import OrganizationalRoleMember
+from .funding_source import FundingSource
+from .organization import Organization
+from .management_body import ManagementBody, getManagementBodies, ManagementBodyPurpose, initManagementBodyPurpose
+from .management_body_member import ManagementBodyMember
+from .communication_means import CommunicationMeans
+from .communication_means_member import CommunicationMeansMember
+from .organizational_role import OrganizationalRole, getLeadOrganizationalRoles, getMemberOrganizationalRoles, getOrganizationalRoles
+from .organizational_role_member import OrganizationalRoleMember
 
 # Search
-from search import *
+from .search import *
 
 # Logging
-from logged_event import LoggedEvent
+from .logged_event import LoggedEvent
 
 # Locks
-from lock import Lock, getLock, createLock, deleteLock, isLockedOut
+from .lock import Lock, getLock, createLock, deleteLock, isLockedOut
 
 # global function involving multiple objects
-from utils import *
+from .utils import *
 
 # model signals
-from signals import account_created_receiver, update_user_projects, update_user_tags
\ No newline at end of file
+from .signals import account_created_receiver, update_user_projects, update_user_tags
\ No newline at end of file
diff --git a/cog/models/auth.py b/cog/models/auth.py
index 420ae041c..efe08e079 100644
--- a/cog/models/auth.py
+++ b/cog/models/auth.py
@@ -3,14 +3,14 @@
 
 from django.contrib.auth.models import User, Permission, Group
 from django.contrib.contenttypes.models import ContentType
-from constants import APPLICATION_LABEL, ROLE_ADMIN, ROLE_CONTRIBUTOR, ROLE_USER
+from .constants import APPLICATION_LABEL, ROLE_ADMIN, ROLE_CONTRIBUTOR, ROLE_USER
 
 # GROUPS
 
 def createGroup(group_name):
     group = Group(name=group_name)
     group.save()
-    print "Created group: %s" % group.name
+    print("Created group: %s" % group.name)
     return group
 
 # method to load a named group from the database, or create a new one if not existing already
@@ -40,11 +40,11 @@ def createProjectPermission(pDesc, pCodeName, groups):
         projectContenType = ContentType.objects.get(app_label=APPLICATION_LABEL, model='project')
         permission = Permission(name=pDesc, codename=pCodeName, content_type=projectContenType)
         permission.save()
-        print 'Created permission=%s...' % permission.codename
+        print('Created permission=%s...' % permission.codename)
         for group in groups:
             group.permissions.add(permission)
             group.save()
-            print '...and associated to group=%s' % group.name
+            print('...and associated to group=%s' % group.name)
         return permission
 
 # method to return a named permission from the database, 
diff --git a/cog/models/bookmark.py b/cog/models/bookmark.py
index caf3e1942..edd2b42c7 100644
--- a/cog/models/bookmark.py
+++ b/cog/models/bookmark.py
@@ -1,5 +1,5 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from cog.models import Post
 
 
@@ -7,7 +7,7 @@ class Bookmark(models.Model):
     
     url = models.URLField('URL', blank=False, max_length=1000)
     name = models.CharField(max_length=1000, blank=False)
-    folder = models.ForeignKey('Folder', blank=False, null=False)
+    folder = models.ForeignKey('Folder', blank=False, null=False, on_delete=models.CASCADE)
     description = models.TextField(max_length=1000, blank=True, null=True)
     order = models.IntegerField(blank=True, default=0)
     # note: do not delete bookmark if notes is deleted
diff --git a/cog/models/collaborator.py b/cog/models/collaborator.py
index a3a184874..8ec3a38af 100644
--- a/cog/models/collaborator.py
+++ b/cog/models/collaborator.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL, RESEARCH_KEYWORDS_MAX_CHARS
-from project import Project
+from .constants import APPLICATION_LABEL, RESEARCH_KEYWORDS_MAX_CHARS
+from .project import Project
 
 class Collaborator(models.Model):
     
@@ -8,7 +8,7 @@ class Collaborator(models.Model):
     last_name = models.CharField(max_length=100, blank=False, default='')
     institution = models.CharField(max_length=100, blank=False, default='')
     researchKeywords = models.CharField(max_length=RESEARCH_KEYWORDS_MAX_CHARS, blank=True, null=True, default='')
-    project = models.ForeignKey(Project, blank=False)
+    project = models.ForeignKey(Project, blank=False, on_delete=models.CASCADE)
     
     # optional picture
     image = models.ImageField(upload_to='photos/', blank=True, null=True)
diff --git a/cog/models/communication_means.py b/cog/models/communication_means.py
index e39d53f3c..8f7ccaea1 100644
--- a/cog/models/communication_means.py
+++ b/cog/models/communication_means.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL, PURPOSE_CV, COMMUNICATION_CV, MEMBERSHIP_CV
-from project import Project
+from .constants import APPLICATION_LABEL, PURPOSE_CV, COMMUNICATION_CV, MEMBERSHIP_CV
+from .project import Project
 
 
 class CommunicationMeans(models.Model):
@@ -23,7 +23,7 @@ class CommunicationMeans(models.Model):
     participationDetails = models.TextField(blank=True, null=True, verbose_name='Participation Details',
                                             help_text='Information about how a person would participate: phone number, '
                                                       'pass code, meeting venue, etc.')
-    project = models.ForeignKey(Project)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
     
     # opt-out privacy option
     internal = models.BooleanField(default=True, null=False)
diff --git a/cog/models/communication_means_member.py b/cog/models/communication_means_member.py
index ef7760ff8..d9dbdd0ea 100644
--- a/cog/models/communication_means_member.py
+++ b/cog/models/communication_means_member.py
@@ -1,12 +1,12 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
-from communication_means import CommunicationMeans
+from .communication_means import CommunicationMeans
 
 class CommunicationMeansMember(models.Model):  
     
-    user = models.ForeignKey(User, blank=False, null=False)
-    communicationMeans = models.ForeignKey(CommunicationMeans, blank=False, null=False)
+    user = models.ForeignKey(User, blank=False, null=False, on_delete=models.CASCADE)
+    communicationMeans = models.ForeignKey(CommunicationMeans, blank=False, null=False, on_delete=models.CASCADE)
             
     class Meta:
         unique_together = (("user", "communicationMeans"),)
diff --git a/cog/models/constants.py b/cog/models/constants.py
index f93661dd4..e2c052d3a 100644
--- a/cog/models/constants.py
+++ b/cog/models/constants.py
@@ -57,7 +57,7 @@
 # create and merge a combined dictionary of organizational roles
 LEAD_ORGANIZATIONAL_ROLES_DICT = dict(LEAD_ORGANIZATIONAL_ROLES)
 MEMBER_ORGANIZATIONAL_ROLES_DICT = dict(MEMBER_ORGANIZATIONAL_ROLES)
-ORGANIZATIONAL_ROLES_DICT = dict( LEAD_ORGANIZATIONAL_ROLES_DICT.items() + MEMBER_ORGANIZATIONAL_ROLES_DICT.items() )
+ORGANIZATIONAL_ROLES_DICT = dict( list(LEAD_ORGANIZATIONAL_ROLES_DICT.items()) + list(MEMBER_ORGANIZATIONAL_ROLES_DICT.items()) )
 
 ROLE_CATEGORY_LEAD = 'Lead'
 ROLE_CATEGORY_MEMBER = 'Member'
@@ -93,7 +93,7 @@
 # create and merge a combined dictionary of management bodies
 STRATEGIC_MANAGEMENT_BODY_DICT = dict(STRATEGIC_MANAGEMENT_BODIES)
 OPERATIONAL_MANAGEMENT_BODY_DICT = dict(OPERATIONAL_MANAGEMENT_BODIES)
-MANAGEMENT_BODY_DICT = dict( STRATEGIC_MANAGEMENT_BODY_DICT.items() + OPERATIONAL_MANAGEMENT_BODY_DICT.items() )
+MANAGEMENT_BODY_DICT = dict( list(STRATEGIC_MANAGEMENT_BODY_DICT.items()) + list(OPERATIONAL_MANAGEMENT_BODY_DICT.items()) )
 
 MEMBERSHIP_TYPES = ('Open','Closed','By Invitation')
 
diff --git a/cog/models/datacart.py b/cog/models/datacart.py
index 149faf7a5..9cf148a64 100644
--- a/cog/models/datacart.py
+++ b/cog/models/datacart.py
@@ -1,5 +1,5 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
 from cog.models.search import Record
 import json
@@ -8,7 +8,7 @@
 
 class DataCart(models.Model):
     
-    user = models.OneToOneField(User, related_name='datacart')
+    user = models.OneToOneField(User, related_name='datacart', on_delete=models.CASCADE)
     
     def contains(self, item_identifier):
         '''Checks whether the data cart contains an item with the given identifier.'''
@@ -20,7 +20,7 @@ class Meta:
         
 class DataCartItem(models.Model):
     
-    cart = models.ForeignKey(DataCart, related_name="items", blank=False, null=False)
+    cart = models.ForeignKey(DataCart, related_name="items", blank=False, null=False, on_delete=models.CASCADE)
     
     # used to enforce uniqueness within a single user datacart
     identifier =  models.CharField(max_length=200, blank=False, null=False)
@@ -51,7 +51,7 @@ def create(datacart, id, metadata):
         item.save()
         
         # save additional metadata            
-        for key, values in metadata.items():
+        for key, values in list(metadata.items()):
             itemKey = DataCartItemMetadataKey(item=item, key=key)
             itemKey.save()
             for value in values:
@@ -109,7 +109,7 @@ def getValue(self, key):
         
 class DataCartItemMetadataKey(models.Model):
 
-    item = models.ForeignKey(DataCartItem, related_name='keys', blank=False, null=False)
+    item = models.ForeignKey(DataCartItem, related_name='keys', blank=False, null=False, on_delete=models.CASCADE)
     key =  models.CharField(max_length=200, blank=False, null=False)
     
     class Meta:
@@ -117,7 +117,7 @@ class Meta:
     
 class DataCartItemMetadataValue(models.Model):
 
-    key = models.ForeignKey(DataCartItemMetadataKey, related_name='values', blank=False, null=False)
+    key = models.ForeignKey(DataCartItemMetadataKey, related_name='values', blank=False, null=False, on_delete=models.CASCADE)
     value =  models.CharField(max_length=1000, blank=True, null=True)
 
     class Meta:
diff --git a/cog/models/doc.py b/cog/models/doc.py
index 221d91ded..a3f248e24 100644
--- a/cog/models/doc.py
+++ b/cog/models/doc.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from project import Project
+from .constants import APPLICATION_LABEL
+from .project import Project
 from django.contrib.auth.models import User
 import os
 from django.conf import settings
@@ -21,7 +21,7 @@ class OverridingFileStorage(FileSystemStorage):
     def save(self, name, content, max_length=None): 
         # must delete current file first  
         if self.exists(name):
-            print 'Deleting existing file=%s' % name
+            print('Deleting existing file=%s' % name)
             self.delete(name)     
         # also, look for Doc objects for the same named file  
         prefix = getattr(settings, "FILEBROWSER_DIRECTORY", "")
@@ -47,7 +47,7 @@ class Doc(models.Model):
     file = models.FileField(upload_to=get_upload_path, storage=ofs, max_length=400)
     publication_date = models.DateTimeField('Date Published', auto_now_add=True)
     update_date = models.DateTimeField('Date Updated', auto_now=True)
-    project = models.ForeignKey(Project)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
     # public/private flag
     is_private = models.BooleanField(verbose_name='Private?', default=False, null=False)
     
diff --git a/cog/models/external_url.py b/cog/models/external_url.py
index 2818bccc6..0b7a9c647 100644
--- a/cog/models/external_url.py
+++ b/cog/models/external_url.py
@@ -1,7 +1,7 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from external_url_conf import externalUrlManager
-from project import Project
+from .constants import APPLICATION_LABEL
+from .external_url_conf import externalUrlManager
+from .project import Project
 
 
 # A reference to an external URL
@@ -12,7 +12,7 @@ class ExternalUrl(models.Model):
     url = models.URLField('URL', blank=False, max_length=1000)
     type = models.CharField(max_length=20, verbose_name='URL Type', blank=False,
                             choices=externalUrlManager.external_url_choices())
-    project = models.ForeignKey(Project)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
     
     def __unicode__(self):
         return "URL Type=%s Title='%s' url='%s' description='%s'" % (self.type, self.title, self.url, self.description)
diff --git a/cog/models/folder.py b/cog/models/folder.py
index e3954abc3..1efb29b91 100644
--- a/cog/models/folder.py
+++ b/cog/models/folder.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from project import Project
+from .constants import APPLICATION_LABEL
+from .project import Project
 from collections import OrderedDict
 from cog.models.dbutils import UnsavedForeignKey
 
@@ -20,10 +20,10 @@
 
 class Folder(models.Model):
 
-    project = UnsavedForeignKey(Project, blank=False)
+    project = UnsavedForeignKey(Project, blank=False, on_delete=models.CASCADE)
     
     name = models.CharField(max_length=200, blank=False)
-    parent = models.ForeignKey('self', blank=True, null=True, related_name='parent_folder')
+    parent = models.ForeignKey('self', blank=True, null=True, related_name='parent_folder', on_delete=models.CASCADE)
     active = models.BooleanField(default=True, blank=False, null=False)
     order = models.IntegerField(blank=True, default=0)
 
@@ -47,7 +47,7 @@ def topParent(self):
             return self.parent.topParent()  # recursion
 
     def isPredefined(self):
-        return self.parent is None or self.name in TOP_SUB_FOLDERS.values()
+        return self.parent is None or self.name in list(TOP_SUB_FOLDERS.values())
 
     class Meta:
         unique_together = (("project", "name"),)
@@ -63,7 +63,7 @@ def getTopFolder(project):
     # name = "%s %s" % (project.short_name, TOP_FOLDER)
     folder, created = Folder.objects.get_or_create(name=TOP_FOLDER, parent=None, project=project, active=True)
     if created:
-        print 'Project=%s: created Top-Level folder=%s' % (project.short_name, folder.name)
+        print('Project=%s: created Top-Level folder=%s' % (project.short_name, folder.name))
     return folder
 
 
@@ -80,7 +80,7 @@ def getTopSubFolders(project):
     _folders = []
     # select pre-defined folders
     for folder in folders:
-        if folder.name in TOP_SUB_FOLDERS.values():
+        if folder.name in list(TOP_SUB_FOLDERS.values()):
             _folders.append(folder)
 
     return _folders
\ No newline at end of file
diff --git a/cog/models/funding_source.py b/cog/models/funding_source.py
index b8a313dfc..2de14683f 100644
--- a/cog/models/funding_source.py
+++ b/cog/models/funding_source.py
@@ -1,13 +1,13 @@
 from django.db import models
-from constants import APPLICATION_LABEL, UPLOAD_DIR_LOGOS
-from project import Project
+from .constants import APPLICATION_LABEL, UPLOAD_DIR_LOGOS
+from .project import Project
 
 class FundingSource(models.Model):
     
     name = models.CharField(max_length=200, blank=False, help_text='Organization or agency that financially supports the project')
     url = models.URLField(max_length=200, blank=True, null=True, help_text='Funding Source URL')
     image = models.ImageField(upload_to=UPLOAD_DIR_LOGOS, blank=True, null=True)
-    project = models.ForeignKey(Project, blank=False)
+    project = models.ForeignKey(Project, blank=False, on_delete=models.CASCADE)
     
     def __unicode__(self):
         return "Project=%s Funding Source=%s" % (self.project, self.name)
diff --git a/cog/models/lock.py b/cog/models/lock.py
index c3a220d03..d3f8311d9 100644
--- a/cog/models/lock.py
+++ b/cog/models/lock.py
@@ -1,7 +1,7 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
-from project_tab import ProjectTab
+from .project_tab import ProjectTab
 from datetime import datetime, timedelta
 
 # default lock lifetime: 30 minutes
@@ -13,7 +13,7 @@ class Lock(models.Model):
     object_type = models.CharField(max_length=100, verbose_name='Object Type', blank=False)
     object_id = models.IntegerField(verbose_name='Object Identifier', blank=False)
     timestamp = models.DateTimeField('Last Update Date', auto_now=True)    
-    owner = models.ForeignKey(User, verbose_name='Owner', blank=False)
+    owner = models.ForeignKey(User, verbose_name='Owner', blank=False, on_delete=models.CASCADE)
         
     def __unicode__(self):
         return "Object type=%s id=%s expiration=%s owner=%s" % (self.object_type, self.object_id, self.get_expiration(), self.owner.get_full_name())
diff --git a/cog/models/logged_event.py b/cog/models/logged_event.py
index 4b41dfcc7..496194b8f 100644
--- a/cog/models/logged_event.py
+++ b/cog/models/logged_event.py
@@ -1,20 +1,20 @@
 from django.db import models
-from constants import APPLICATION_LABEL, SIGNAL_OBJECT_CREATED, SIGNAL_OBJECT_UPDATED, SIGNAL_OBJECT_DELETED
+from .constants import APPLICATION_LABEL, SIGNAL_OBJECT_CREATED, SIGNAL_OBJECT_UPDATED, SIGNAL_OBJECT_DELETED
 from django.contrib.auth.models import User
 from django.db.models.signals import post_save
 from django.core.signals import request_finished
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.dispatch import receiver
-from post import Post, post_signal
-from doc import Doc
-from news import News
+from .post import Post, post_signal
+from .doc import Doc
+from .news import News
 
 
 class LoggedEvent(models.Model):
     '''Class that represents an important event that is logged to the database.'''
 
-    user = models.ForeignKey(User, blank=False)
-    project = models.ForeignKey('Project', blank=False)
+    user = models.ForeignKey(User, blank=False, on_delete=models.CASCADE)
+    project = models.ForeignKey('Project', blank=False, on_delete=models.CASCADE)
     title = models.CharField(max_length=200, blank=False)
     description = models.CharField(max_length=200, blank=False)
     url = models.URLField(blank=True)
diff --git a/cog/models/management_body.py b/cog/models/management_body.py
index c0732966d..3a75ada0a 100644
--- a/cog/models/management_body.py
+++ b/cog/models/management_body.py
@@ -39,7 +39,7 @@ class ManagementBody(models.Model):
     category = models.CharField(max_length=50, blank=True, null=False, default=MANAGEMENT_BODY_CATEGORY_STRATEGIC,
                                 choices=MANAGEMENT_BODY_CATEGORIES_CV, verbose_name='Category',
                                 help_text='Strategic or Operational management body purpose.')
-    project = models.ForeignKey(Project)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
 
     # sort list of members my last name and ignore case
     def members(self):
@@ -91,18 +91,18 @@ def getManagementBodies(project, category):
 def initManagementBodyPurpose():
     """Function to populate the database with the necessary instances of ManagementBodyPurpose."""
     
-    for purpose, order in STRATEGIC_MANAGEMENT_BODY_DICT.items():
+    for purpose, order in list(STRATEGIC_MANAGEMENT_BODY_DICT.items()):
         try:
             mbp = ManagementBodyPurpose.objects.get(purpose=purpose, category=MANAGEMENT_BODY_CATEGORY_STRATEGIC)
         except ManagementBodyPurpose.DoesNotExist:
             mbp = ManagementBodyPurpose(purpose=purpose, order=order, category=MANAGEMENT_BODY_CATEGORY_STRATEGIC)
             mbp.save()
-            print "Created management body purpose: %s" % mbp
+            print("Created management body purpose: %s" % mbp)
             
-    for purpose, order in OPERATIONAL_MANAGEMENT_BODY_DICT.items():
+    for purpose, order in list(OPERATIONAL_MANAGEMENT_BODY_DICT.items()):
         try:
             mbp = ManagementBodyPurpose.objects.get(purpose=purpose, category=MANAGEMENT_BODY_CATEGORY_OPERATIONAL)
         except ManagementBodyPurpose.DoesNotExist:
             mbp = ManagementBodyPurpose(purpose=purpose, order=order, category=MANAGEMENT_BODY_CATEGORY_OPERATIONAL)
             mbp.save()
-            print "Created management body purpose: %s" % mbp
\ No newline at end of file
+            print("Created management body purpose: %s" % mbp)
\ No newline at end of file
diff --git a/cog/models/management_body_member.py b/cog/models/management_body_member.py
index d5af246a2..5ae4c4d74 100644
--- a/cog/models/management_body_member.py
+++ b/cog/models/management_body_member.py
@@ -1,12 +1,12 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
-from management_body import ManagementBody
+from .management_body import ManagementBody
 
 class ManagementBodyMember(models.Model):
     
-    user = models.ForeignKey(User, blank=False, null=False)
-    managementBody = models.ForeignKey(ManagementBody, blank=False, null=False)
+    user = models.ForeignKey(User, blank=False, null=False, on_delete=models.CASCADE)
+    managementBody = models.ForeignKey(ManagementBody, blank=False, null=False, on_delete=models.CASCADE)
             
     class Meta:
         unique_together = (("user", "managementBody"),)    
diff --git a/cog/models/membership.py b/cog/models/membership.py
index 0c8f260a6..06832058b 100644
--- a/cog/models/membership.py
+++ b/cog/models/membership.py
@@ -1,13 +1,13 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User, Group
 import django.dispatch
 
 # Object holding user requests to join a group
 class MembershipRequest(models.Model):
     
-    user = models.ForeignKey(User)    
-    group = models.ForeignKey(Group)   
+    user = models.ForeignKey(User, on_delete=models.CASCADE)    
+    group = models.ForeignKey(Group, on_delete=models.CASCADE)   
     date = models.DateTimeField('Request Date', auto_now=True)
 
     class Meta:
diff --git a/cog/models/navbar.py b/cog/models/navbar.py
index 3fe33b813..074b6729e 100644
--- a/cog/models/navbar.py
+++ b/cog/models/navbar.py
@@ -3,7 +3,7 @@
 i.e. for the project pre-defined pages.
 """
 
-from external_url_conf import EXTERNAL_URL_TYPES, externalUrlManager
+from .external_url_conf import EXTERNAL_URL_TYPES, externalUrlManager
 
 # dictionary containing (page key, page URL)
 TABS = {"ABOUTUS": "aboutus", "MISSION": "mission",
diff --git a/cog/models/news.py b/cog/models/news.py
index 33fd27ab3..f55a99f50 100644
--- a/cog/models/news.py
+++ b/cog/models/news.py
@@ -1,7 +1,7 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
-from project import Project
+from .project import Project
 
 # A piece of News about a Project
 class News(models.Model):
@@ -11,7 +11,7 @@ class News(models.Model):
     author = models.ForeignKey(User, null=True, on_delete=models.SET_NULL)
     publication_date = models.DateTimeField('Date Published', auto_now_add=True)
     update_date = models.DateTimeField('Date Updated', auto_now=True)
-    project = models.ForeignKey(Project, verbose_name='About Project')
+    project = models.ForeignKey(Project, verbose_name='About Project', on_delete=models.CASCADE)
     other_projects = models.ManyToManyField(Project, verbose_name='Projects Notified', related_name='other_news', blank=True)
     
     def __unicode__(self):
diff --git a/cog/models/organization.py b/cog/models/organization.py
index c05c47e2c..346fbf570 100644
--- a/cog/models/organization.py
+++ b/cog/models/organization.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL, UPLOAD_DIR_LOGOS
-from project import Project
+from .constants import APPLICATION_LABEL, UPLOAD_DIR_LOGOS
+from .project import Project
 
 
 class Organization(models.Model):
@@ -8,7 +8,7 @@ class Organization(models.Model):
     name = models.CharField(max_length=200, blank=False, help_text='Project or organization that collaborates on this project')
     url = models.URLField(max_length=200, blank=True, null=True, help_text='Organization URL')
     image = models.ImageField(upload_to=UPLOAD_DIR_LOGOS, blank=True, null=True)
-    project = models.ForeignKey(Project, blank=False)
+    project = models.ForeignKey(Project, blank=False, on_delete=models.CASCADE)
     
     def __unicode__(self):
         return "Project=%s Organization=%s" % (self.project, self.name)
diff --git a/cog/models/organizational_role.py b/cog/models/organizational_role.py
index 180bea883..ef3ea19d9 100644
--- a/cog/models/organizational_role.py
+++ b/cog/models/organizational_role.py
@@ -1,6 +1,6 @@
 from django.db import models
-from constants import APPLICATION_LABEL, ORGANIZATIONAL_ROLE_CV, ORGANIZATIONAL_ROLE_CATEGORIES_CV
-from project import Project
+from .constants import APPLICATION_LABEL, ORGANIZATIONAL_ROLE_CV, ORGANIZATIONAL_ROLE_CATEGORIES_CV
+from .project import Project
 from django.contrib.auth.models import User
 from cog.models.constants import ROLE_CATEGORY_LEAD, ROLE_CATEGORY_MEMBER, ORGANIZATIONAL_ROLES_DICT, LEAD_ORGANIZATIONAL_ROLES_DICT
 
@@ -11,7 +11,7 @@ class OrganizationalRole(models.Model):
     title = models.CharField(max_length=200, blank=True, null=True, verbose_name='Title',  help_text='Optional string used to succinctly describe an organizational role.')
     description = models.TextField(blank=True, null=True, verbose_name='Description', help_text='Long description providing extra information about an organizational role.')
     category = models.CharField(max_length=50, blank=True, null=False, default='Member', choices=ORGANIZATIONAL_ROLE_CATEGORIES_CV, verbose_name='Category', help_text='Lead or Member role.')
-    project = models.ForeignKey(Project)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
 
     def set_category(self, dict={}):
         """Method to select the object category from the other fields. """
diff --git a/cog/models/organizational_role_member.py b/cog/models/organizational_role_member.py
index c9681343c..d71eea141 100644
--- a/cog/models/organizational_role_member.py
+++ b/cog/models/organizational_role_member.py
@@ -1,12 +1,12 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from django.contrib.auth.models import User
-from organizational_role import OrganizationalRole
+from .organizational_role import OrganizationalRole
 
 class OrganizationalRoleMember(models.Model):
     
-    user = models.ForeignKey(User, blank=False, null=False)
-    organizationalRole = models.ForeignKey(OrganizationalRole, blank=False, null=False)
+    user = models.ForeignKey(User, blank=False, null=False, on_delete=models.CASCADE)
+    organizationalRole = models.ForeignKey(OrganizationalRole, blank=False, null=False, on_delete=models.CASCADE)
             
     class Meta:
         unique_together = (("user", "organizationalRole"),)    
diff --git a/cog/models/peer_site.py b/cog/models/peer_site.py
index 7bf500c07..f0bbe46c0 100644
--- a/cog/models/peer_site.py
+++ b/cog/models/peer_site.py
@@ -10,7 +10,7 @@
 
 class PeerSite(models.Model):
     
-    site = models.OneToOneField(Site, blank=False, null=False, related_name='peersite')
+    site = models.OneToOneField(Site, blank=False, null=False, related_name='peersite', on_delete=models.CASCADE)
     enabled = models.BooleanField(default=False, null=False)
     
     class Meta:
diff --git a/cog/models/post.py b/cog/models/post.py
index a205ae00e..45a9c4e4a 100644
--- a/cog/models/post.py
+++ b/cog/models/post.py
@@ -1,9 +1,9 @@
 from django.db import models
-from constants import APPLICATION_LABEL, SIGNAL_OBJECT_CREATED, SIGNAL_OBJECT_UPDATED, SIGNAL_OBJECT_DELETED
-from project import Project
+from .constants import APPLICATION_LABEL, SIGNAL_OBJECT_CREATED, SIGNAL_OBJECT_UPDATED, SIGNAL_OBJECT_DELETED
+from .project import Project
 from django.contrib.auth.models import User
-from doc import Doc
-from topic import Topic
+from .doc import Doc
+from .topic import Topic
 import django.dispatch
 
 # A web site post, which can be of different types
@@ -27,7 +27,7 @@ class Post(models.Model):
         publication_date = models.DateTimeField('Date Published', auto_now_add=True)
         update_date = models.DateTimeField('Date Updated')
         # project context
-        project = models.ForeignKey(Project)
+        project = models.ForeignKey(Project, on_delete=models.CASCADE)
         # order of post within project index
         order = models.IntegerField(blank=True, null=False, default=0)
         # optional topic
diff --git a/cog/models/project.py b/cog/models/project.py
index e95d00732..68702a7a2 100644
--- a/cog/models/project.py
+++ b/cog/models/project.py
@@ -1,23 +1,23 @@
 
 from cog.utils import smart_truncate
-from constants import *
-from navbar import *
+from .constants import *
+from .navbar import *
 from django.conf import settings
 from django.contrib.auth.models import User, Permission, Group
 from django.db import models
 from django.db.models import Q
 from django.forms import Textarea
-from membership import MembershipRequest
+from .membership import MembershipRequest
 from os.path import basename
 from cog.models.user_profile import UserProfile
 from cog.models.topic import Topic
 from cog.models.project_tag import ProjectTag
-from urllib import quote, unquote
+from urllib.parse import quote, unquote
 import os
 import sys
 import re
 from django.contrib.sites.models import Site
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from collections import OrderedDict
 from django.core.exceptions import ObjectDoesNotExist
 from cog.models.auth import (getAdminGroupName, getContributorGroupName, getUserGroupName, 
@@ -35,7 +35,7 @@ class Project(models.Model):
     long_name = models.CharField(max_length=120, unique=True, help_text='Fully spelled project name.')
     description = models.TextField(blank=False, null=True, help_text='A short paragraph that describes the project.')
     
-    site = models.ForeignKey(Site, default=settings.SITE_ID)
+    site = models.ForeignKey(Site, default=settings.SITE_ID, on_delete=models.CASCADE)
     
     # optional attributes
     mission = models.TextField(blank=True, help_text='Succinctly describes why the project exists and what it does.')
@@ -237,7 +237,7 @@ def getPublicUsers(self):
         pubUsers = []
         for user in users:
             try:
-                print 'Checking user=%s' % user  # TODO:FixME
+                print('Checking user=%s' % user)  # TODO:FixME
                 if not user.profile.private:
                     pubUsers.append(user)
             except ObjectDoesNotExist:
@@ -430,7 +430,7 @@ def getProjectsAndRolesForUsers(user, includeRemote=True):
                 elif group.name.endswith('_users'):
                     projects[project.short_name].append(ROLE_USER)
         except ObjectDoesNotExist:
-            print "WARNING: cannot retrieve project for group=%s" % group
+            print("WARNING: cannot retrieve project for group=%s" % group)
             pass
         
     return projects
@@ -463,6 +463,6 @@ def create_upload_directory(project):
     fb_upload_dir = os.path.join(settings.MEDIA_ROOT, settings.FILEBROWSER_DIRECTORY, project.short_name.lower())
     if not os.path.exists(fb_upload_dir):
         os.makedirs(fb_upload_dir)
-        print 'Project Upload directory created: %s' % fb_upload_dir
+        print('Project Upload directory created: %s' % fb_upload_dir)
 
 
diff --git a/cog/models/project_impact.py b/cog/models/project_impact.py
index d3f970549..5e6cd59e1 100644
--- a/cog/models/project_impact.py
+++ b/cog/models/project_impact.py
@@ -1,10 +1,10 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from project import Project
+from .constants import APPLICATION_LABEL
+from .project import Project
 
 class ProjectImpact(models.Model):
     
-    project = models.ForeignKey(Project, blank=False, related_name='impacts')
+    project = models.ForeignKey(Project, blank=False, related_name='impacts', on_delete=models.CASCADE)
     title = models.CharField(max_length=200, help_text='Title for this impact.', blank=False, null=False, default='')
     description = models.TextField(blank=False, null=False, verbose_name='Project Impact', help_text='Describe a major impact of this project in its field.')
     # IMPORTANT: NEVER USE A DEFAULT WITH A FORMSET, OTHERWISE has_changed=True for empty forms!
diff --git a/cog/models/project_tab.py b/cog/models/project_tab.py
index 658d6239f..6fd9f9b3b 100644
--- a/cog/models/project_tab.py
+++ b/cog/models/project_tab.py
@@ -1,15 +1,15 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from navbar import PROJECT_PAGES, DEFAULT_TABS
-from project import Project
-from django.core.urlresolvers import reverse
+from .constants import APPLICATION_LABEL
+from .navbar import PROJECT_PAGES, DEFAULT_TABS
+from .project import Project
+from django.urls import reverse
 from cog.models.dbutils import UnsavedForeignKey
 
     
 # Tab displayed in project top navigation menu
 class ProjectTab(models.Model):
         
-    project = UnsavedForeignKey(Project, blank=False, null=False, related_name="tabs")
+    project = UnsavedForeignKey(Project, blank=False, null=False, related_name="tabs", on_delete=models.CASCADE)
     
     # the URL of a corresponding project page
     url = models.CharField(max_length=200, verbose_name='URL', blank=True, unique=True, default='')
@@ -18,7 +18,7 @@ class ProjectTab(models.Model):
     # whether or not the tab will be displayed
     active = models.BooleanField(default=True, null=False, blank=False)
     # optional parent tab (null for top-level tabs)
-    parent = models.ForeignKey('self', blank=True, null=True)
+    parent = models.ForeignKey('self', blank=True, null=True, on_delete=models.CASCADE)
     
     def __unicode__(self):
         return "Project Tab label='%s', url='%s', active=%s" % (self.label, self.url, self.active)
diff --git a/cog/models/project_tag.py b/cog/models/project_tag.py
index 6d7382269..e1a5e399b 100644
--- a/cog/models/project_tag.py
+++ b/cog/models/project_tag.py
@@ -1,5 +1,5 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 
 MAX_PROJECT_TAG_LENGTH = 20
 
diff --git a/cog/models/project_topic.py b/cog/models/project_topic.py
index 641643c6a..483e3b2e3 100644
--- a/cog/models/project_topic.py
+++ b/cog/models/project_topic.py
@@ -1,12 +1,12 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from topic import Topic
-from project import Project
+from .constants import APPLICATION_LABEL
+from .topic import Topic
+from .project import Project
 
 # intermediate model for Project-Topic association
 class ProjectTopic(models.Model):
-    topic = models.ForeignKey(Topic)
-    project = models.ForeignKey(Project)
+    topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
+    project = models.ForeignKey(Project, on_delete=models.CASCADE)
     # topic order within project index
     order = models.IntegerField(blank=False, null=False, default=0)
     
diff --git a/cog/models/search.py b/cog/models/search.py
index 5c85cd14c..0ed87c861 100644
--- a/cog/models/search.py
+++ b/cog/models/search.py
@@ -1,5 +1,5 @@
 from django.db import models
-import ConfigParser
+import configparser
 from datetime import datetime
 import os
 
@@ -35,9 +35,9 @@ def getSortedValues(self):
         return [(value, self.values[value]) for value in sorted(self.values.keys())]
         
     def printme(self):
-        print "Facet key=%s label=%s" % (self.key, self.label)
-        for value, counts in self.values.items():
-            print "\tValue=%s counts=%d" % (value, counts)
+        print("Facet key=%s label=%s" % (self.key, self.label))
+        for value, counts in list(self.values.items()):
+            print("\tValue=%s counts=%d" % (value, counts))
             
 class SearchInput:
     
@@ -58,7 +58,7 @@ def addConstraint(self, name, value):
             self.constraints[name].append(value)
         except KeyError:
             self.constraints[name] = [value]
-        print "constraint name=%s value(s)=%s" % (name, self.constraints[name])
+        print("constraint name=%s value(s)=%s" % (name, self.constraints[name]))
         
     def setConstraint(self, name, values):
         self.constraints[name] = values
@@ -98,11 +98,11 @@ def isEmpty(self):
         return self.query == '' and len(self.constraints)==0
         
     def printme(self):
-        print "Search Input"
-        print "\t Query=%s Type=%s Offset=%d Limit=%d Max Version=%s Min Version=%s" % (self.query, self.type, self.offset, self.limit, 
-                                                                                        self.max_version, self.min_version)
-        for key, values in self.constraints.items():
-            print "\t Constraint key=%s value(s)=%s" % (key, values)
+        print("Search Input")
+        print("\t Query=%s Type=%s Offset=%d Limit=%d Max Version=%s Min Version=%s" % (self.query, self.type, self.offset, self.limit, 
+                                                                                        self.max_version, self.min_version))
+        for key, values in list(self.constraints.items()):
+            print("\t Constraint key=%s value(s)=%s" % (key, values))
         
         
 class SearchOutput:
@@ -116,8 +116,8 @@ def setFacet(self, facet):
         self.facets[facet.key] = facet
         
     def printme(self):
-        print "Search Output: total number of results=%d" % self.counts
-        for facet in self.facets.values():
+        print("Search Output: total number of results=%d" % self.counts)
+        for facet in list(self.facets.values()):
             facet.printme()
         for record in self.results:
             record.printme()
@@ -136,9 +136,9 @@ def addField(self, name, value):
             self.fields[name] = [value]
             
     def printme(self):
-        print "Record id=%s" % self.id
-        for name, values in self.fields.items():
-            print "\tField name=%s values=%s" % (name, values)
+        print("Record id=%s" % self.id)
+        for name, values in list(self.fields.items()):
+            print("\tField name=%s values=%s" % (name, values))
                         
 class FacetProfile:
     
@@ -156,7 +156,7 @@ def __init__(self, facetGroups):
         self.map = {}
         for group in self.facetGroups:
             self.keys = self.keys + group.keys
-            self.map = dict( self.map.items() + group.map.items() )
+            self.map = dict( list(self.map.items()) + list(group.map.items()) )
                         
     def getAllKeys(self):
         """Returns a list of keys over all its facet groups."""
@@ -217,14 +217,14 @@ def __init__(self, facetProfile, fixedConstraints, searchService,
         self.localFlag = localFlag
         
     def printme(self):
-        print 'Search Configuration Service:%s' % self.searchService
-        print 'Search Configuration Facets:'
+        print('Search Configuration Service:%s' % self.searchService)
+        print('Search Configuration Facets:')
         for facetGroup in self.facetProfile.facetGroups:
-            print "\tFacet Group=%s" % facetGroup.name
+            print("\tFacet Group=%s" % facetGroup.name)
             for key in facetGroup.getKeys():
-                print "\t\tFacet key=%s, label=%s" % (key, facetGroup.getLabel(key))
-        print 'Search Configuration Fixed Constraints=%s' % self.fixedConstraints
-        print 'Search Configuration options: show replica checkbox: %s, show latest checkbox: %s, show local checkbox:%s' % (self.replicaFlag, self.latestFlag, self.localFlag)
+                print("\t\tFacet key=%s, label=%s" % (key, facetGroup.getLabel(key)))
+        print('Search Configuration Fixed Constraints=%s' % self.fixedConstraints)
+        print('Search Configuration options: show replica checkbox: %s, show latest checkbox: %s, show local checkbox:%s' % (self.replicaFlag, self.latestFlag, self.localFlag))
     
 class SearchMappings(object):
     """Class that reads facet option mappings from a local configuration file,
@@ -237,7 +237,7 @@ def __init__(self):
         CONFIGFILEPATH = os.path.join(cog_config_dir, 'cog_search.cfg')
         
         self.mappings = {}
-        config = ConfigParser.RawConfigParser()
+        config = configparser.RawConfigParser()
         try:
             config.read( CONFIGFILEPATH )
             for facet_key in config.sections():
@@ -249,8 +249,8 @@ def __init__(self):
                 self.mappings[facet_key] = fmap
             #print 'Loaded search mappinsg from file: %s' % filepath
         except Exception as e:
-            print "Search mappings file not found"
-            print e
+            print("Search mappings file not found")
+            print(e)
             
     def getFacetOptionLabel(self, facet_key, facet_option):
         """Returns the facet_option for the given facet_key if found,
diff --git a/cog/models/search_facet.py b/cog/models/search_facet.py
index f19e9a8c0..5e5a81a51 100644
--- a/cog/models/search_facet.py
+++ b/cog/models/search_facet.py
@@ -1,11 +1,11 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from search_group import SearchGroup
+from .constants import APPLICATION_LABEL
+from .search_group import SearchGroup
 
 # Search facet displayed in user interface
 class SearchFacet(models.Model):
     
-    group = models.ForeignKey(SearchGroup, related_name="facets", blank=False, null=True)
+    group = models.ForeignKey(SearchGroup, related_name="facets", blank=False, null=True, on_delete=models.CASCADE)
     
     key =  models.CharField(max_length=40, blank=False)
     label =  models.CharField(max_length=40, blank=False)
diff --git a/cog/models/search_group.py b/cog/models/search_group.py
index 38147eb15..9e759f7d0 100644
--- a/cog/models/search_group.py
+++ b/cog/models/search_group.py
@@ -1,13 +1,13 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from search_profile import SearchProfile
+from .constants import APPLICATION_LABEL
+from .search_profile import SearchProfile
 
 # Group of search facets
 class SearchGroup(models.Model):
     
     DEFAULT_NAME = 'default'
     
-    profile = models.ForeignKey(SearchProfile, related_name="groups", blank=False, null=False)
+    profile = models.ForeignKey(SearchProfile, related_name="groups", blank=False, null=False, on_delete=models.CASCADE)
     name =  models.CharField(max_length=40, null=False, blank=False, default=DEFAULT_NAME)
     order = models.IntegerField(blank=True, default=0)
     
diff --git a/cog/models/search_profile.py b/cog/models/search_profile.py
index e8ee72edb..c78387020 100644
--- a/cog/models/search_profile.py
+++ b/cog/models/search_profile.py
@@ -1,11 +1,11 @@
 from django.db import models
-from constants import APPLICATION_LABEL
-from project import Project
+from .constants import APPLICATION_LABEL
+from .project import Project
 
 # Project-specific search configuration (persisted to the database)
 class SearchProfile(models.Model):
     
-    project = models.OneToOneField(Project, blank=False, null=False)
+    project = models.OneToOneField(Project, blank=False, null=False, on_delete=models.CASCADE)
     
     # name that identifies this configuration
     #name = models.CharField(max_length=50, blank=False, unique=True, default='')
diff --git a/cog/models/signals.py b/cog/models/signals.py
index 452f4ca2d..e2ceead40 100644
--- a/cog/models/signals.py
+++ b/cog/models/signals.py
@@ -29,7 +29,7 @@ def account_created_receiver(sender, **kwargs):
             # change the username
             lastPartOfOpenid = userp.openid().split("/")[-1]
             username = createUsername(lastPartOfOpenid)
-            print "New user: changing the username from: %s to: %s" % (userp.user.username, username)
+            print("New user: changing the username from: %s to: %s" % (userp.user.username, username))
             userp.user.username = username
             userp.user.save()
 
@@ -46,7 +46,7 @@ def update_user_projects(user):
     and save the updated information in the local database.
     '''
 
-    if user.is_authenticated():
+    if user.is_authenticated:
         
         # current user groups in local database
         ugroups = user.groups.all()
@@ -57,13 +57,13 @@ def update_user_projects(user):
         # add new memberships for remote projects
         remoteGroups = [] # updated list of remote groups
         for (project, roles) in projTuples:
-            print 'Updating membership for user: %s project: %s roles: %s' % (user.profile.openid(), project.short_name, roles)
+            print('Updating membership for user: %s project: %s roles: %s' % (user.profile.openid(), project.short_name, roles))
             
             for role in roles:
                 group = project.getGroup(role)
                 remoteGroups.append(group)
                 if not group in ugroups:
-                    print 'Adding group: %s to user: %s' % (group, user)
+                    print('Adding group: %s to user: %s' % (group, user))
                     user.groups.add(group)
                    
         # persist changes to local database 
@@ -76,10 +76,10 @@ def update_user_projects(user):
                 # do not change local projects
                 if not project.isLocal():
                     if not group in remoteGroups:
-                        print 'Removing group: %s from user: %s' % (group, user)
+                        print('Removing group: %s from user: %s' % (group, user))
                         user.groups.remove( group )
             except ObjectDoesNotExist:
-                print 'WARNING: cannot retrieve project for group=%s, removing obsolete group' % group
+                print('WARNING: cannot retrieve project for group=%s, removing obsolete group' % group)
                 user.groups.remove( group )
             
         # persist changes to local database
@@ -92,7 +92,7 @@ def update_user_tags(user):
         
         openid = user.profile.openid()
         url = "http://%s/share/user/?openid=%s" % (user.profile.site.domain, user.profile.openid())
-        print 'Updating user tags: querying URL=%s' % url
+        print('Updating user tags: querying URL=%s' % url)
         jobj = getJson(url)
         
         if jobj is not None and openid in jobj['users'] and 'project_tags' in jobj['users'][openid]:
@@ -111,7 +111,7 @@ def update_user_tags(user):
             userProfile.tags = tags
             userProfile.save()
             transaction.commit()
-            print 'User: %s updated for tags: %s' % (user, tags)
+            print('User: %s updated for tags: %s' % (user, tags))
     
 # NOTE: connecting the login signal is not needed because every time the user logs in,
 # the session is refreshed and updating of projects is triggered already by the CoG session middleware
diff --git a/cog/models/topic.py b/cog/models/topic.py
index 4f1d7b04e..13c32826f 100644
--- a/cog/models/topic.py
+++ b/cog/models/topic.py
@@ -1,5 +1,5 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 
 # A category to group Posts
 class Topic(models.Model):
diff --git a/cog/models/user_profile.py b/cog/models/user_profile.py
index 3cc6f2a22..36d50f4f7 100644
--- a/cog/models/user_profile.py
+++ b/cog/models/user_profile.py
@@ -1,11 +1,11 @@
 from django.db import models
 from django.contrib.auth.models import User
-from constants import APPLICATION_LABEL, RESEARCH_KEYWORDS_MAX_CHARS, RESEARCH_INTERESTS_MAX_CHARS
+from .constants import APPLICATION_LABEL, RESEARCH_KEYWORDS_MAX_CHARS, RESEARCH_INTERESTS_MAX_CHARS
 from django.conf import settings
 
 from cog.utils import hasText
 from django.contrib.sites.models import Site
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from cog.utils import getJson
 from cog.models.peer_site import getPeerSites
 from cog.models.project_tag import ProjectTag
@@ -14,10 +14,10 @@
 class UserProfile(models.Model):
 
     # user
-    user = models.OneToOneField(User, related_name='profile')
+    user = models.OneToOneField(User, related_name='profile', on_delete=models.CASCADE)
     
     # node (using the django site object)
-    site = models.ForeignKey(Site, default=1)
+    site = models.ForeignKey(Site, default=1, on_delete=models.CASCADE)
 
     # additional mandatory fields
     institution = models.CharField(max_length=100, blank=False, default='')
@@ -146,7 +146,7 @@ def discoverSiteForUser(openid):
         url = "http://%s/share/user/?openid=%s" % (site.domain, openid)
         jobj = getJson(url)
         if jobj is not None:
-            for key, value in jobj['users'].items():
+            for key, value in list(jobj['users'].items()):
                 if str(value['home_site_domain']) == site.domain:
                     return site  # node found
             
@@ -166,10 +166,10 @@ def getDataCartsForUser(openid):
     #for site in Site.objects.all():  # loop over all sites (e.g. nodes) in database. Note: includes current node
     for site in getPeerSites():  # loop over nodes that are federated
         url = "http://%s/share/user/?openid=%s" % (site.domain, openid)
-        print 'Querying for datacart: url=%s' % url
+        print('Querying for datacart: url=%s' % url)
         jobj = getJson(url)
         if jobj is not None:
-            for key, value in jobj['users'].items():
+            for key, value in list(jobj['users'].items()):
                 dcs[ site ] = int( value['datacart']['size'] )
             
     return dcs
diff --git a/cog/models/user_url.py b/cog/models/user_url.py
index 578307b06..c545c4d10 100644
--- a/cog/models/user_url.py
+++ b/cog/models/user_url.py
@@ -1,5 +1,5 @@
 from django.db import models
-from constants import APPLICATION_LABEL
+from .constants import APPLICATION_LABEL
 from cog.models import UserProfile
 
 class UserUrl(models.Model):   
@@ -7,7 +7,7 @@ class UserUrl(models.Model):
     
     url = models.URLField('URL', blank=False, null=False, max_length=1000)
     name = models.CharField(max_length=200, blank=False, null=False)
-    profile = models.ForeignKey(UserProfile, blank=False, null=False)
+    profile = models.ForeignKey(UserProfile, blank=False, null=False, on_delete=models.CASCADE)
     
     class Meta:
         app_label = APPLICATION_LABEL
diff --git a/cog/models/utils.py b/cog/models/utils.py
index 7e10a64f7..f053a4094 100644
--- a/cog/models/utils.py
+++ b/cog/models/utils.py
@@ -1,25 +1,25 @@
-from project import Project
-from collaborator import Collaborator
-from project_topic import ProjectTopic
-from search_profile import SearchProfile
-from communication_means import CommunicationMeans
-from search_facet import SearchFacet
-from search_group import SearchGroup
-from post import Post
-from bookmark import Bookmark
-from doc import Doc
-from navbar import PROJECT_PAGES, DEFAULT_TABS
+from .project import Project
+from .collaborator import Collaborator
+from .project_topic import ProjectTopic
+from .search_profile import SearchProfile
+from .communication_means import CommunicationMeans
+from .search_facet import SearchFacet
+from .search_group import SearchGroup
+from .post import Post
+from .bookmark import Bookmark
+from .doc import Doc
+from .navbar import PROJECT_PAGES, DEFAULT_TABS
 from django.conf import settings
 from django.utils.timezone import now
-from news import News
+from .news import News
 from django.db.models import Q
 from django.contrib.contenttypes.models import ContentType
-from folder import Folder, getTopFolder, TOP_SUB_FOLDERS
+from .folder import Folder, getTopFolder, TOP_SUB_FOLDERS
 from cog.models.constants import DEFAULT_SEARCH_FACETS
-from project_tab import ProjectTab
+from .project_tab import ProjectTab
 import shutil
 import os
-from urllib import quote
+from urllib.parse import quote
 
 
 # method to retrieve all news for a given project, ordered by original publication date
@@ -63,7 +63,7 @@ def site_index(project):
 # -) page numbers start at 1 (for Home)
 def init_site_index(project):
     
-    print 'Initializing project index'
+    print('Initializing project index')
     project.topics.clear()
     
     # list all top-level project pages, order by topic first, then title
@@ -94,7 +94,7 @@ def create_project_search_profile(project):
     try:
         profile = project.searchprofile
     except SearchProfile.DoesNotExist:
-        print 'Configuring the project search profile'
+        print('Configuring the project search profile')
         # assign default URL, if available
         url = getattr(settings, "DEFAULT_SEARCH_URL", "")
         profile = SearchProfile(project=project, url=url)
@@ -104,7 +104,7 @@ def create_project_search_profile(project):
         group.save()
         # assign default facets
         facets = DEFAULT_SEARCH_FACETS
-        for key, label in facets.items():
+        for key, label in list(facets.items()):
             facet = SearchFacet(key=key, label=label, group=group)
             facet.save()
         project.searchprofile = profile
@@ -159,7 +159,7 @@ def create_project_page(url, project):
                         if _page[0] == 'Logistics':
                             page.title = '%s Agenda' % project.short_name
                             page.save()
-                        print "Created project page: %s" % url
+                        print("Created project page: %s" % url)
                         return page
     return None
 
@@ -194,7 +194,7 @@ def get_or_create_default_search_group(project):
     try:
         group = SearchGroup.objects.filter(profile=profile).filter(name=SearchGroup.DEFAULT_NAME)[0]
     except IndexError:
-        print 'Creating default search group for project=%s' % project.short_name
+        print('Creating default search group for project=%s' % project.short_name)
         group = SearchGroup(profile=profile, name=SearchGroup.DEFAULT_NAME, order=len(list(profile.groups.all())))
         group.save()
     return group    
@@ -228,13 +228,13 @@ def get_or_create_project_tabs(project, save=True):
                     active = False
                 tab = ProjectTab(project=project, label=label, url=url, active=active)
                 if save:
-                    print "Creating tab= %s" % tab
+                    print("Creating tab= %s" % tab)
                     tab.save() 
                     # assign parent tab
                     if i > 0:
                         tab.parent = tablist[0]
                         tab.save()
-                        print "Assigned parent tab=%s to child tab=%s" % (tablist[0], tab)
+                        print("Assigned parent tab=%s to child tab=%s" % (tablist[0], tab))
 
             tablist.append(tab)
         tabs.append(tablist)
@@ -249,7 +249,7 @@ def setActiveProjectTabs(tabs, request, save=False):
         # Home tab MUST always be active
         if tab.label.endswith("Home"):
             tab.active = True
-        elif "tab_%s" % tab.label in request.POST.keys():
+        elif "tab_%s" % tab.label in list(request.POST.keys()):
             tab.active = True
         else:
             tab.active = False
@@ -273,11 +273,11 @@ def createOrUpdateProjectSubFolders(project, request=None):
     
     topFolder = getTopFolder(project)
     
-    for name in TOP_SUB_FOLDERS.values():
+    for name in list(TOP_SUB_FOLDERS.values()):
         folder, created = Folder.objects.get_or_create(name=name, parent=topFolder, project=project)
         if created:
-            print 'Project=%s: created top-level folder=%s' % (project.short_name, folder.name)
-        if request is not None and ("folder_%s" % folder.name) in request.POST.keys():
+            print('Project=%s: created top-level folder=%s' % (project.short_name, folder.name))
+        if request is not None and ("folder_%s" % folder.name) in list(request.POST.keys()):
             folder.active = True
         else:
             folder.active = False
@@ -287,7 +287,7 @@ def getBookmarkFromDoc(doc):
     '''Returns the first Bookmark with URL matching the Document path.'''
     
     url_fragment = quote(doc.path, safe="%/:=&?~#+!$,;'@()*[]")
-    print 'Looking for bookmark that contains URL fragment: %s' % url_fragment
+    print('Looking for bookmark that contains URL fragment: %s' % url_fragment)
     bookmarks = Bookmark.objects.filter(url__contains=url_fragment)
     for bookmark in bookmarks:
         return bookmark
@@ -298,7 +298,7 @@ def getDocFromBookmark(bookmark):
     
     if 'site_media/' in bookmark.url:
         _, url_fragment = bookmark.url.split('site_media/', 1)
-        print 'Looking for doc that contains path: %s' % url_fragment
+        print('Looking for doc that contains path: %s' % url_fragment)
         docs = Doc.objects.filter(path__contains=url_fragment)
         for doc in docs:
             return doc
@@ -318,7 +318,7 @@ def delete_doc(doc):
     # remove possible associated resource
     bookmark = getBookmarkFromDoc(doc)
     if bookmark is not None:
-        print 'Deleting associated bookmark: %s' % bookmark.url
+        print('Deleting associated bookmark: %s' % bookmark.url)
         bookmark.delete()
         
     # obtain document full path (before deleting object from database)
@@ -331,7 +331,7 @@ def delete_doc(doc):
     # delete document from file system
     for fp in [fullpath, fullpath2]:
         if os.path.exists(fp):
-            print 'Deleting document=%s' % fp
+            print('Deleting document=%s' % fp)
             os.remove(fp)
     
     # also delete possible thumbnail files (created by File Browser)
@@ -349,47 +349,47 @@ def deleteProject(project, dryrun=True, rmdir=False):
     Utility method to delete a project and associated objects, media.
     """
     
-    print "Deleting project=%s" % project.short_name
+    print("Deleting project=%s" % project.short_name)
            
     # delete project User group, permissions
     ug = project.getUserGroup()
     for p in ug.permissions.all():
-        print '\tDeleting permission: %s' % p
+        print('\tDeleting permission: %s' % p)
         if not dryrun:
             p.delete()
-    print '\tDeleting group: %s' % ug
+    print('\tDeleting group: %s' % ug)
     if not dryrun:
         ug.delete()
         
     # delete project Admin group, permissions
     ag = project.getAdminGroup()
     for p in ag.permissions.all():
-        print '\tDeleting permission: %s' % p
+        print('\tDeleting permission: %s' % p)
         if not dryrun:
             p.delete()
-    print '\tDeleting group: %s' % ag
+    print('\tDeleting group: %s' % ag)
     if not dryrun:
         ag.delete()
 
     # delete project Contributor group, permissions
     cg = project.getContributorGroup()
     for p in cg.permissions.all():
-        print '\tDeleting permission: %s' % p
+        print('\tDeleting permission: %s' % p)
         if not dryrun:
             p.delete()
-    print '\tDeleting group: %s' % cg
+    print('\tDeleting group: %s' % cg)
     if not dryrun:
         cg.delete()
 
     if rmdir:
         media_dir = os.path.join(settings.MEDIA_ROOT, settings.FILEBROWSER_DIRECTORY, project.short_name.lower())
-        print "\tRemoving directory tree: %s" % media_dir
+        print("\tRemoving directory tree: %s" % media_dir)
         if not dryrun:
             try:
                 shutil.rmtree(media_dir)
             except OSError as e:
-                print e
+                print(e)
     
-    print '\tDeleting project: %s' % project
+    print('\tDeleting project: %s' % project)
     if not dryrun:
         project.delete()
\ No newline at end of file
diff --git a/cog/notification.py b/cog/notification.py
index 057e1060d..4ccb4e140 100644
--- a/cog/notification.py
+++ b/cog/notification.py
@@ -24,16 +24,16 @@ def __init__(self):
                 self.username = siteManager.get('EMAIL_USERNAME', section=SECTION_EMAIL)
                 self.password = siteManager.get('EMAIL_PASSWORD', section=SECTION_EMAIL)
                 self.security = siteManager.get('EMAIL_SECURITY', section=SECTION_EMAIL)
-                print 'Using email server=%s' %  self.server
-                print 'Using email port=%s' %  self.port
-                print 'Using email sender=%s' %  self.sender
-                print 'Using email username=%s' %  self.username
+                print('Using email server=%s' %  self.server)
+                print('Using email port=%s' %  self.port)
+                print('Using email sender=%s' %  self.sender)
+                print('Using email username=%s' %  self.username)
                 #print 'Using email password=%s' %  self.password
-                print 'Using email security=%s' %  self.security
+                print('Using email security=%s' %  self.security)
                 self.init = True
             
         if not self.init:
-            print "Email configuration not found, email notification disabled"
+            print("Email configuration not found, email notification disabled")
             
 
 # module scope email configuration
@@ -74,10 +74,10 @@ def __init__ (self, toAddress, subject, message, fromAddress=None, mime_type='pl
     def run(self):
         
         #print "From: %s" % self.fromAddress
-        print "To: %s" % self.toAddress
-        print "Subject: %s" % self.subject
-        print "Message: %s" % self.message
-        print "Mime Type: %s" % self.mime_type
+        print("To: %s" % self.toAddress)
+        print("Subject: %s" % self.subject)
+        print("Message: %s" % self.message)
+        print("Mime Type: %s" % self.mime_type)
         
         # use local mail server
         #toUser.email_user(subject, message, from_email=fromAddress)
@@ -100,4 +100,4 @@ def run(self):
                 s.login(emailConfig.username, emailConfig.password )
             s.sendmail(emailConfig.sender, [self.toAddress], msg.as_string())
             s.quit()
-            print 'Email sent.'
+            print('Email sent.')
diff --git a/cog/plugins/esgf/registry.py b/cog/plugins/esgf/registry.py
index 133314d2f..04ac6fd5c 100644
--- a/cog/plugins/esgf/registry.py
+++ b/cog/plugins/esgf/registry.py
@@ -20,18 +20,14 @@
 #import certifi
 NS = "http://www.esgf.org/whitelist"
 
-class WhiteList(object):
-
-    __metaclass__ = abc.ABCMeta
+class WhiteList(object, metaclass=abc.ABCMeta):
 
     @abc.abstractmethod
     def trust(self, openid):
         '''Returns true if an openid can be trusted, false otherwise.'''
         pass
     
-class KnownProvidersDict(object):
-    
-    __metaclass__ = abc.ABCMeta
+class KnownProvidersDict(object, metaclass=abc.ABCMeta):
     
     @abc.abstractmethod
     def idpDict(self):
@@ -84,7 +80,7 @@ def _reload(self, force=False):
     
             if force or modtime > self.modtime:
     
-                print 'Loading known IdPs from file: %s, last modified: %s' % (self.filepath, modtime)
+                print('Loading known IdPs from file: %s, last modified: %s' % (self.filepath, modtime))
                 self.modtime = modtime
                 idps = {}
     
@@ -104,7 +100,7 @@ def _reload(self, force=False):
                     if name is not None and len(name.strip()) > 0:
                         url = idp.find('URL').text
                         idps[name] = url
-                        print 'Using known IdP: name=%s url=%s' % (name, url)
+                        print('Using known IdP: name=%s url=%s' % (name, url))
     
                 # switch the dictionary of knwon providers
                 self.idps = idps
@@ -136,7 +132,7 @@ def __init__(self, filepath_string):
             try:
                 self._reload(filepath, force=True)
             except ParseError as e:
-                print e # print error from parsing single white-list files and continue
+                print(e) # print error from parsing single white-list files and continue
 
 
     def _reload(self, filepath, force=False):
@@ -146,7 +142,7 @@ def _reload(self, filepath, force=False):
 
         if force or modtime > self.modtimes[filepath]:
 
-            print 'Loading IdP white list: %s, last modified: %s' % (filepath, modtime)
+            print('Loading IdP white list: %s, last modified: %s' % (filepath, modtime))
             self.modtimes[filepath] = modtime
             idps = []
 
@@ -162,7 +158,7 @@ def _reload(self, filepath, force=False):
                 if match:
                     idp = match.group(1)
                     idps.append(idp.lower())
-                    print 'Using trusted IdP: %s' % idp
+                    print('Using trusted IdP: %s' % idp)
 
             # switch the list for this file path
             self.idps[filepath] = idps
@@ -202,7 +198,7 @@ def reload(self, delete=False):
         
         if self.filepath is not None and os.path.exists(self.filepath):
             
-            print('Updating list of CoG sites from: %s (delete: %s)' % (self.filepath, delete) )
+            print(('Updating list of CoG sites from: %s (delete: %s)' % (self.filepath, delete) ))
             
             # current site - must not be updated from file list
             current_site = Site.objects.get_current()
@@ -221,7 +217,7 @@ def reload(self, delete=False):
                     name = site.attrib['name']
                     domain = site.attrib['domain']
                     domains.append(domain)
-                    print 'Updating site domain: %s name: %s' % (domain, name)
+                    print('Updating site domain: %s name: %s' % (domain, name))
                     
                     # update Site objects
                     try:
@@ -230,25 +226,25 @@ def reload(self, delete=False):
                             # update site
                             _site.name = name
                             _site.save()
-                            print('Updated site: %s' % _site)
+                            print(('Updated site: %s' % _site))
                     except ObjectDoesNotExist:
                         _site = Site.objects.create(name=name, domain=domain)
-                        print 'Created site: %s' % _site
+                        print('Created site: %s' % _site)
                         
                     # update PeerSite objects
                     try:
                         peersite = PeerSite.objects.get(site=_site)
                     except ObjectDoesNotExist:
                         peersite = PeerSite.objects.create(site=_site, enabled=False)
-                    print '\tPeer site: %s' % peersite
+                    print('\tPeer site: %s' % peersite)
                             
             # clean up stale sites
             if delete:
                 for peer in PeerSite.objects.all():
                     if peer.site.domain not in domains:
                         if peer.site != current_site:
-                            print 'Stale peer site found at domain: %s' % peer.site.domain + ", deleting it..."
+                            print('Stale peer site found at domain: %s' % peer.site.domain + ", deleting it...")
                             peer.site.delete() # will also delete the PeerSite object on cascade
 
         else:
-            print 'WARNING: File %s does not exist, skipping update of ESGF peer nodes' % self.filepath
\ No newline at end of file
+            print('WARNING: File %s does not exist, skipping update of ESGF peer nodes' % self.filepath)
\ No newline at end of file
diff --git a/cog/plugins/esgf/security.py b/cog/plugins/esgf/security.py
index 7f4f7f969..2f92bf997 100644
--- a/cog/plugins/esgf/security.py
+++ b/cog/plugins/esgf/security.py
@@ -69,7 +69,7 @@ def createGroup(self, name, description='', visible=True, automatic_approval=Fal
             session = self.Session()
             
             group = session.query(ESGFGroup).filter( func.lower(ESGFGroup.name) == func.lower(name) ).one()
-            print "Group with name=%s already exists" % group.name
+            print("Group with name=%s already exists" % group.name)
             created = False
             
             return group
@@ -125,13 +125,13 @@ def insertEsgfUser(self, userProfile):
     
                 session.add(esgfUser)
                 session.commit()
-                print 'Inserted user with openid=%s into ESGF database' % openid
+                print('Inserted user with openid=%s into ESGF database' % openid)
     
             finally:
                 session.close()
 
         else:
-            print 'User with openid: %s already existing in ESGF database, no action taken' % esgfUser.openid
+            print('User with openid: %s already existing in ESGF database, no action taken' % esgfUser.openid)
             pass
 
     def getUserByOpenid(self, openid):
@@ -184,7 +184,7 @@ def listUsers(self):
         for user in users:
             parts = user.openid.split('/')
             new_username = parts[-1]
-            print 'Updating user: openid=%s new username=%s' % (user.openid, new_username)
+            print('Updating user: openid=%s new username=%s' % (user.openid, new_username))
             user.username = new_username
             
         session.commit()
@@ -228,7 +228,7 @@ def updatePassword(self, user, clearTextPwd):
                     session = self.Session()
                     encPasword = md5_crypt.encrypt(clearTextPwd)
                     esgfUser.password = encPasword
-                    print 'Updated ESGF password for user with openid: %s' % openid
+                    print('Updated ESGF password for user with openid: %s' % openid)
                     session.add(esgfUser)
                     session.commit()
                     session.close()
@@ -251,7 +251,7 @@ def updateUser(self, user_profile):
                     esgfUser.city = user_profile.city
                     esgfUser.state = user_profile.state
                     esgfUser.country = user_profile.country
-                    print 'Updated ESGF data for user with openid: %s' % openid
+                    print('Updated ESGF data for user with openid: %s' % openid)
                     session.add(esgfUser)
                     session.commit()
                     session.close()
@@ -265,7 +265,7 @@ def deleteUser(self, user):
                 esgfUser = self.getUserByOpenid(openid)
                 
                 if esgfUser is not None:
-                    print 'Deleting ESGF user with openid=%s' % openid    
+                    print('Deleting ESGF user with openid=%s' % openid)    
                     session = self.Session()
                     # delete user permissions
                     permissions = session.query(ESGFPermission).filter(ESGFPermission.user_id==esgfUser.id)
diff --git a/cog/plugins/globus/directory_transfer.py b/cog/plugins/globus/directory_transfer.py
index 20eafedf9..178f827fc 100644
--- a/cog/plugins/globus/directory_transfer.py
+++ b/cog/plugins/globus/directory_transfer.py
@@ -42,20 +42,20 @@ def arguments(argv):
 	dlocation = args.download_location
 
 	if '#' not in uendpoint:
-		print "Please supply a valid Globus endpoint (local host)"
+		print("Please supply a valid Globus endpoint (local host)")
 		sys.exit()
 	if '#' not in gendpoint:
-		print "Please supply a valid Globus endpoint (remote host)"
+		print("Please supply a valid Globus endpoint (remote host)")
 	if '/' in uendpoint:
-		print "Do not include the download path in the local endpoint name, please use the -p option"
+		print("Do not include the download path in the local endpoint name, please use the -p option")
 		sys.exit()
 	if '/' in gendpoint:
-		print "Do not include the download path in the remote endpoint name, please use the -p option"
+		print("Do not include the download path in the remote endpoint name, please use the -p option")
 	if '#' in path:
-		print "The '#' character is invalid in your path, please re-enter"
+		print("The '#' character is invalid in your path, please re-enter")
 		sys.exit()
 	if '#' in dlocation:
-		print "The '#' character is invalid in your download location, please re-enter"
+		print("The '#' character is invalid in your download location, please re-enter")
 	if path[-1] != '/':
 		path = path + '/'
 	if path[0] != '/':
diff --git a/cog/plugins/globus/download.py b/cog/plugins/globus/download.py
index d6b6f94c4..4383f9a3f 100644
--- a/cog/plugins/globus/download.py
+++ b/cog/plugins/globus/download.py
@@ -9,10 +9,10 @@
 
 def listEndpoints(gendpointDict):
 
-    endNames = gendpointDict.keys()
-    print "Endpoints involved:"
+    endNames = list(gendpointDict.keys())
+    print("Endpoints involved:")
     for thisEndName in endNames:
-        print thisEndName
+        print(thisEndName)
 
 def arguments(argv):
 
@@ -42,10 +42,10 @@ def arguments(argv):
     listonly = args.list_endpoints
 
     if '/' in uendpoint:
-        print "Do not include the download path in the endpoint name, please use the -p option"
+        print("Do not include the download path in the endpoint name, please use the -p option")
         sys.exit()
     if '#' in upath:
-        print "The '#' character is invalid in your path, please re-enter"
+        print("The '#' character is invalid in your path, please re-enter")
         sys.exit()
     if upath[0] != '/' and upath != '/~/':
         upath = '/' + upath
@@ -56,7 +56,7 @@ def getFiles(gendpointDict, uendpoint, username, upath):
 
     label = str(uuid4())
 
-    endNames = gendpointDict.keys()
+    endNames = list(gendpointDict.keys())
 
     for thisEndName in endNames:
 
diff --git a/cog/plugins/globus/transfer.py b/cog/plugins/globus/transfer.py
index ce6e1bdd8..a0306e6d5 100644
--- a/cog/plugins/globus/transfer.py
+++ b/cog/plugins/globus/transfer.py
@@ -7,19 +7,16 @@
 from datetime import datetime, timedelta
 from cog.site_manager import siteManager
 if siteManager.isGlobusEnabled():    
-    from globusonline.transfer.api_client import Transfer
-    from globusonline.transfer.api_client import TransferAPIClient
-    from globusonline.transfer.api_client import TransferAPIError
-    from globusonline.transfer.api_client import x509_proxy
+    from globus_sdk import TransferData
 import os
-import urlparse
+import urllib.parse
 
 DOWNLOAD_SCRIPT = "download.py"
 
 def generateGlobusDownloadScript(download_map):
 
-    print "Generating script for downloading files: "
-    print download_map
+    print("Generating script for downloading files: ")
+    print(download_map)
 
     # read script 'download.py' located in same directory as this module
     scriptFile = os.path.join(os.path.dirname(__file__), DOWNLOAD_SCRIPT)
@@ -30,66 +27,58 @@ def generateGlobusDownloadScript(download_map):
     return script
 
 
-def activateEndpoint(api_client, endpoint, myproxy_server=None, username=None, password=None, cert=None, key=None):
-    if (not myproxy_server or not password) and (not myproxy_server or not cert):
+def activateEndpoint(transfer_client, endpoint, myproxy_server=None, username=None, password=None):
+    if not myproxy_server or not password:
         # Try to autoactivate the endpoint
-        code, reason, result = api_client.endpoint_autoactivate(endpoint, if_expires_in=2880)
-        print "Endpoint Activation: %s. %s: %s" % (endpoint, result["code"], result["message"])
+        result = transfer_client.endpoint_autoactivate(endpoint, if_expires_in=2880)
+        print("Endpoint Activation: %s. %s: %s" % (endpoint, result["code"], result["message"]))
         if result["code"] == "AutoActivationFailed":
             return (False, "")
         return (True, "")
 
-    code, reason, reqs = api_client.endpoint_activation_requirements(endpoint)
-
-    # Activate the endpoint using an X.509 user credential stored by esgf-idp in /tmp/x509up_<idp_hostname>_<username>
-    if cert and key:
-        cred_file = "/tmp/x509up_%s_%s" % (myproxy_server, username)
-        with open(cred_file, 'w') as cred:
-            cred.write(cert)
-            cred.write(key)
-        public_key = reqs.get_requirement_value("delegate_proxy", "public_key")
-        try:
-            proxy = x509_proxy.create_proxy_from_file(cred_file, public_key, lifetime_hours=72)
-        except Exception as e:
-            print "Could not activate the endpoint: %s. Error: %s" % (endpoint, str(e))
-            return False
-        reqs.set_requirement_value("delegate_proxy", "proxy_chain", proxy)
-    else:
-        # Activate the endpoint using MyProxy server method
-        reqs.set_requirement_value("myproxy", "hostname", myproxy_server)
-        reqs.set_requirement_value("myproxy", "username", username)
-        reqs.set_requirement_value("myproxy", "passphrase", password)
-        reqs.set_requirement_value("myproxy", "lifetime_in_hours", "168")
+    requirements = transfer_client.endpoint_get_activation_requirements(endpoint)
+    requirements_json = requirements.data
+
+    # Activate the endpoint using MyProxy server method
+    for i, d in enumerate(requirements_json["DATA"]):
+        if d["type"] == "myproxy":
+            if d["name"] == "hostname":
+                requirements_json["DATA"][i]["value"] = myproxy_server
+            elif d["name"] == "username":
+                requirements_json["DATA"][i]["value"] = username
+            elif d["name"] == "passphrase":
+                requirements_json["DATA"][i]["value"] = password
+            elif d["name"] == "lifetime_in_hours":
+                requirements_json["DATA"][i]["value"] = "168"
 
     try:
-        code, reason, result = api_client.endpoint_activate(endpoint, reqs)
+        result = transfer_client.endpoint_activate(endpoint, requirements_json)
     except Exception as e:
-        print "Could not activate the endpoint: %s. Error: %s" % (endpoint, str(e))
+        print("Could not activate the endpoint: %s. Error: %s" % (endpoint, str(e)))
         return (False, str(e))
-    if code != 200:
-        print "Could not aactivate the endpoint: %s. Error: %s - %s" % (endpoint, result["code"], result["message"])
+    if result["code"] != "Activated.MyProxyCredential":
+        print("Could not aactivate the endpoint: %s. Error: %s - %s" % (endpoint, result["code"], result["message"]))
         return (False, result["message"])
 
-    print "Endpoint Activation: %s. %s: %s" % (endpoint, result["code"], result["message"])
+    print("Endpoint Activation: %s. %s: %s" % (endpoint, result["code"], result["message"]))
 
     return (True, "")
 
 
-def submitTransfer(api_client, source_endpoint, source_files, target_endpoint, target_directory):
+def submitTransfer(transfer_client, source_endpoint, source_files, target_endpoint, target_directory):
     '''
     Method to submit a data transfer request to Globus.
     '''
     
-    # obtain a submission id from Globus
-    code, message, data = api_client.transfer_submission_id()
-    submission_id = data["value"]
-    print "Obtained transfer submission id: %s" % submission_id
-    
     # maximum time for completing the transfer
     deadline = datetime.utcnow() + timedelta(days=10)
     
     # create a transfer request
-    transfer_task = Transfer(submission_id, source_endpoint, target_endpoint, deadline)
+    if "%23" in target_endpoint:
+        target_endpoint = target_endpoint.replace("%23", "#")
+    transfer_task = TransferData(transfer_client, source_endpoint, target_endpoint, deadline=deadline)
+    print("Obtained transfer submission id: %s" % transfer_task["submission_id"])
+
     for source_file in source_files:
         source_directory, filename = os.path.split(source_file)
         target_file = os.path.join(target_directory, filename) 
@@ -97,11 +86,11 @@ def submitTransfer(api_client, source_endpoint, source_files, target_endpoint, t
     
     # submit the transfer request
     try:
-        code, reason, data = api_client.transfer(transfer_task)
+        data = transfer_client.submit_transfer(transfer_task)
         task_id = data["task_id"]
-        print "Submitted transfer task with id: %s" % task_id
+        print("Submitted transfer task with id: %s" % task_id)
     except Exception as e:
-        print "Could not submit the transfer. Error: %s" % str(e)
+        print("Could not submit the transfer. Error: %s" % str(e))
         task_id = "Could not submit the transfer. Please contact the ESGF node admin to investigate the issue."
     
     return task_id
diff --git a/cog/project_manager.py b/cog/project_manager.py
index 3a21e1e8e..77a53a7dc 100644
--- a/cog/project_manager.py
+++ b/cog/project_manager.py
@@ -58,7 +58,7 @@ def _associateProjects(self, objList, apDictList):
                                                site__domain=site_domain)
                 objList.add(aproject)
             except Project.DoesNotExist: # correct short name, wrong site ?
-                print 'Associated project does not exist in local database: short_name=%s site_domain=%s, will ignore' % (apdict['short_name'], apdict['site_domain'])
+                print('Associated project does not exist in local database: short_name=%s site_domain=%s, will ignore' % (apdict['short_name'], apdict['site_domain']))
                 pass 
                     
         
@@ -79,14 +79,14 @@ def _harvest(self, jobj):
             
             remote_site, created = Site.objects.get_or_create(domain=sdict['domain'])
             if created:
-                print 'Created remote site: %s' % remote_site
+                print('Created remote site: %s' % remote_site)
             else:
-                print 'Remote site %s already existing' % remote_site
+                print('Remote site %s already existing' % remote_site)
             #remote_site.name = sdict["name"] # don't change the site 'name', keep value from esgf_cogs.xml instead
             #remote_site.save()
                         
             # first loop to create ALL projects first
-            for key, pdict in jobj["projects"].items():
+            for key, pdict in list(jobj["projects"].items()):
                               
                 short_name = pdict['short_name']
                 long_name = pdict['long_name']
@@ -97,17 +97,17 @@ def _harvest(self, jobj):
                     
                     if not Project.objects.filter(short_name__iexact=short_name).exists(): # avoid conflicts with existing projects, from ANY site
                         # create new project
-                        print 'Creating project=%s (%s) for site=%s in local database' % (short_name, long_name, remote_site)
+                        print('Creating project=%s (%s) for site=%s in local database' % (short_name, long_name, remote_site))
                         try:
                             Project.objects.create(short_name=short_name, long_name=long_name, site=remote_site, active=True)
-                            print 'Created project=%s for site=%s in local database' % (short_name, remote_site)
+                            print('Created project=%s for site=%s in local database' % (short_name, remote_site))
                         except Exception as e:
-                            print e # ignore errors while creating any one project from remote site, continue iteration
+                            print(e) # ignore errors while creating any one project from remote site, continue iteration
                     else:
-                        print 'Project with name:%s already exists (local or remote)' % short_name
+                        print('Project with name:%s already exists (local or remote)' % short_name)
             
             # second loop to update project attributes and associations
-            for key, pdict in jobj["projects"].items():
+            for key, pdict in list(jobj["projects"].items()):
                 
                 short_name = pdict['short_name']
                 long_name = pdict['long_name']
@@ -121,7 +121,7 @@ def _harvest(self, jobj):
                     try:
                         # load existing project from remote site
                         project = Project.objects.get(short_name=short_name, site=remote_site)
-                        print 'Loaded project: %s from site: %s' % (short_name, site_domain)
+                        print('Loaded project: %s from site: %s' % (short_name, site_domain))
                         
                         # update project attributes
                         project.long_name = long_name
@@ -140,9 +140,9 @@ def _harvest(self, jobj):
                         
                         # update project associations
                         self._associateProjects(project.peers, pdict['peers'])
-                        print 'Updated project peers=%s' % project.peers.all()
+                        print('Updated project peers=%s' % project.peers.all())
                         self._associateProjects(project.parents, pdict['parents'])
-                        print 'Updated project parents=%s' % project.parents.all()                    
+                        print('Updated project parents=%s' % project.parents.all())                    
                         
                         project.save()
                         
diff --git a/cog/services/SolrSerializer.py b/cog/services/SolrSerializer.py
index 8c9e6637c..8dc58028d 100644
--- a/cog/services/SolrSerializer.py
+++ b/cog/services/SolrSerializer.py
@@ -19,7 +19,7 @@ def serialize(input, output):
         strEl = SubElement(docEl, "str", attrib={ "name":"id" } )
         strEl.text = record.id
         
-        for key, values in record.fields.items():
+        for key, values in list(record.fields.items()):
             # <str name="type">Dataset</str>
             # single-valued fields (as from Solr schema)
             if key == 'url' or key=='type':
@@ -41,9 +41,9 @@ def serialize(input, output):
     facetFieldsEl  = SubElement(facetCountsEl, "lst", attrib={ "name": "facet_fields" })
     
     # loop over facets
-    for key, facet in output.facets.items():
+    for key, facet in list(output.facets.items()):
         facetEl = SubElement(facetFieldsEl, "lst", attrib={ "name": key })
-        for value, counts in facet.getValues().items():
+        for value, counts in list(facet.getValues().items()):
             facetSubEl = SubElement(facetEl, "int", attrib={ "name": value })
             facetSubEl.text = str(counts)
     
@@ -115,7 +115,7 @@ def deserialize(xml, facetProfile):
                             
         
     except (ValueError, LookupError) as err:
-        print "Error: %s" % err    
+        print("Error: %s" % err)    
     return output
 
 def _encode_field_value(record, name, value):
@@ -141,7 +141,7 @@ def _encode_field_value(record, name, value):
             elif name=='xlink':
                 # NOTE: 'xlink' metadata is renamed to 'url' metadata
                 if parts[2] == 'pid':
-                    record.addField('url', (parts[0], 'application/pid', 'PID'))
+                    record.addField('url', (parts[0].replace('/hd1.', '/hdl.'), 'application/pid', 'PID'))
                 elif parts[2] == 'citation':
                     record.addField('url', (parts[0], 'application/citation', 'Citation'))
                 elif parts[2] == 'technote':
@@ -158,4 +158,4 @@ def _encode_field_value(record, name, value):
         else:
             record.addField(name, value.strip())  
 
-    
\ No newline at end of file
+    
diff --git a/cog/services/membership.py b/cog/services/membership.py
index 975c23010..3d7418314 100644
--- a/cog/services/membership.py
+++ b/cog/services/membership.py
@@ -9,7 +9,7 @@
 from django.contrib.auth.models import User, Group, Permission
 from cog.models import (MembershipRequest, ManagementBodyMember, OrganizationalRoleMember, 
                         getProjectForGroup, CommunicationMeansMember, LoggedEvent)
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 import django.dispatch
 
 # return codes
@@ -35,7 +35,7 @@ def cancelMembershipRequest(user, group):
     mrlist = MembershipRequest.objects.filter(group=group).filter(user=user)
     if len(mrlist)>0:
         for mr in mrlist:
-            print 'Cancelling membership request for user=%s group=%s' % (user.username, group.name)
+            print('Cancelling membership request for user=%s group=%s' % (user.username, group.name))
             mr.delete()
             
 # Method to cancel ALL membership requests for a given user, project
@@ -51,7 +51,7 @@ def addMembership(user, group, admin=None):
     
     if not group in user.groups.all():
         user.groups.add(group)
-        print "Enrolled user=%s in group=%s" % (user.username, group.name)
+        print("Enrolled user=%s in group=%s" % (user.username, group.name))
         cancelMembershipRequests(user, project)
         # log event
         if admin is not None:
@@ -62,7 +62,7 @@ def addMembership(user, group, admin=None):
         return RESULT_SUCCESS
     
     else:
-        print "User=%s is already enrolled in group=%s" % (user.username, group.name)
+        print("User=%s is already enrolled in group=%s" % (user.username, group.name))
         cancelMembershipRequests(user, project)
         return RESULT_DUPLICATE
 
@@ -78,7 +78,7 @@ def cancelMembership(user, group, admin=None):
            
         # first remove user from that group
         user.groups.remove(group)
-        print "Removed user=%s from group=%s" % (user.username, group.name)
+        print("Removed user=%s from group=%s" % (user.username, group.name))
         
         # if user is not part of the project any more, remove from all project management bodies
         project = getProjectForGroup(group)
@@ -86,17 +86,17 @@ def cancelMembership(user, group, admin=None):
             # Management Bodies
             objs = ManagementBodyMember.objects.filter(user=user).filter(managementBody__project=project)
             for obj in objs:
-                print 'Deleting ManagementBodyMember for project=%s user=%s managementBody=%s' % (project, user, obj.managementBody.title)
+                print('Deleting ManagementBodyMember for project=%s user=%s managementBody=%s' % (project, user, obj.managementBody.title))
                 obj.delete()
             # Organization Roles
             objs = OrganizationalRoleMember.objects.filter(user=user).filter(organizationalRole__project=project)
             for obj in objs:
-                print 'Deleting OrganizationalRoleMember for project=%s user=%s organizationalRole=%s' % (project, user, obj.organizationalRole.title)
+                print('Deleting OrganizationalRoleMember for project=%s user=%s organizationalRole=%s' % (project, user, obj.organizationalRole.title))
                 obj.delete()
             # Communication Means
             objs = CommunicationMeansMember.objects.filter(user=user).filter(communicationMeans__project=project)
             for obj in objs:
-                print 'Deleting CommunicationMeansMember for project=%s user=%s communicationMeans=%s' % (project, user, obj.communicationMeans.title)
+                print('Deleting CommunicationMeansMember for project=%s user=%s communicationMeans=%s' % (project, user, obj.communicationMeans.title))
                 obj.delete()
             
         # log event
@@ -110,5 +110,5 @@ def cancelMembership(user, group, admin=None):
         return RESULT_SUCCESS
     
     else:
-        print "User=%s not found in group=%s" % (user.username, group.name)
+        print("User=%s not found in group=%s" % (user.username, group.name))
         return RESULT_NOT_FOUND
\ No newline at end of file
diff --git a/cog/services/registration/__init__.py b/cog/services/registration/__init__.py
index e60dffc6b..ca8b642f7 100644
--- a/cog/services/registration/__init__.py
+++ b/cog/services/registration/__init__.py
@@ -1,2 +1,2 @@
-from registration import RegistrationService
-from registration_impl import ESGFRegistrationServiceImpl, esgfRegistrationServiceImpl
\ No newline at end of file
+from .registration import RegistrationService
+from .registration_impl import ESGFRegistrationServiceImpl, esgfRegistrationServiceImpl
\ No newline at end of file
diff --git a/cog/services/registration/registration.py b/cog/services/registration/registration.py
index 3f211f977..f57a096d9 100644
--- a/cog/services/registration/registration.py
+++ b/cog/services/registration/registration.py
@@ -6,10 +6,8 @@
 
 import abc
 
-class RegistrationService(object):
+class RegistrationService(object, metaclass=abc.ABCMeta):
     
-    __metaclass__ = abc.ABCMeta
-
     @abc.abstractmethod
     def createGroup(self, name, description='', visible=True, automatic_approval=False):
         '''
diff --git a/cog/services/search.py b/cog/services/search.py
index 18cf6a4ba..7ba36b9d8 100644
--- a/cog/services/search.py
+++ b/cog/services/search.py
@@ -1,5 +1,4 @@
-import urllib, urllib2
-from string import join
+import urllib.request, urllib.parse, urllib.error, urllib.request, urllib.error, urllib.parse
 
 # search service that queries a Solr server through the ESGF RESTful search API
 class SolrSearchService:
@@ -30,7 +29,7 @@ def search(self, searchInput, allFacets=False):
         if searchInput.min_version:
             params.append( ('min_version', searchInput.min_version.strip()) )
 
-        for key, values in searchInput.constraints.items():
+        for key, values in list(searchInput.constraints.items()):
             for value in values:
                 params.append( (key, value) )
 
@@ -39,13 +38,13 @@ def search(self, searchInput, allFacets=False):
             params.append( ("facets", "*") )
         else:
             if len(self.facets)>0:
-                facetlist = join([facet.key for facet in self.facets], ',')
+                facetlist = ','.join([facet.key for facet in self.facets])
                 params.append( ("facets", facetlist) )
                 
-        url = self.url+"?"+urllib.urlencode(params)
-        print 'ESGF search URL=%s' % url
-        fh = urllib2.urlopen( url )
-        xml = fh.read().decode("UTF-8")
+        url = self.url+"?"+urllib.parse.urlencode(params)
+        print('ESGF search URL=%s' % url)
+        fh = urllib.request.urlopen( url )
+        xml = fh.read()
    
         # return search URL and corresponding results as XML
         return (url, xml)
\ No newline at end of file
diff --git a/cog/site_manager.py b/cog/site_manager.py
index 557381675..120293a0e 100644
--- a/cog/site_manager.py
+++ b/cog/site_manager.py
@@ -1,6 +1,6 @@
 import os
 import time
-import ConfigParser
+import configparser
 import logging
 
 from cog.constants import (SECTION_ESGF, SECTION_GLOBUS, SECTION_PID)
@@ -22,16 +22,16 @@ def __init__(self):
             logging.info("Waiting to read configuration file: %s" % SiteManager.CONFIGFILEPATH )
             time.sleep(1)
 
-        self.config = ConfigParser.ConfigParser(allow_no_value=True)
+        self.config = configparser.ConfigParser(allow_no_value=True)
         # location of site specific settings configuration file
         self.cog_config_dir = SiteManager.COG_CONFIG_DIR
         try:
             config = self.config.read( SiteManager.CONFIGFILEPATH )
             logging.info("Site manager: using CoG settings from file(s): %s" % config)
-            print 'Initialized CoG settings from file: %s' % SiteManager.CONFIGFILEPATH
+            print('Initialized CoG settings from file: %s' % SiteManager.CONFIGFILEPATH)
             
         except Exception as e:
-            print "Error reading site settings configuration file: %s" % SiteManager.CONFIGFILEPATH
+            print("Error reading site settings configuration file: %s" % SiteManager.CONFIGFILEPATH)
 
     def get(self, name, section='DEFAULT', default=None):
         '''Method that retrieves a settings value from a specified section of the configuration file.'''
diff --git a/cog/templates/cog/datacart/_citation_js.html b/cog/templates/cog/datacart/_citation_js.html
index fd2c62d91..7d275ef16 100644
--- a/cog/templates/cog/datacart/_citation_js.html
+++ b/cog/templates/cog/datacart/_citation_js.html
@@ -53,6 +53,10 @@
             var title = jsonResponse.titles[0];
             var publisher = jsonResponse.publisher;
             var publication_year = jsonResponse.publicationYear;
+            var license = "unknown";
+            if (jsonResponse.rightsList.length > 0) {
+               license = jsonResponse.rightsList[0].rights;
+            }
 
             // point to DOI landing page if it is a DOI
             if(id_type=="DOI") {
@@ -85,6 +89,9 @@
             html += "<div style='text-align:left'><b>Title:</b> "+title+"</div>";
             html += "<div style='text-align:left'><b>Publisher:</b> "+publisher+"</div>";
             html += "<div style='text-align:left'><b>Publication Year:</b> "+publication_year+"</div>";
+            if(license != "unknown") {
+                html += "<div style='text-align:left'><b>License:</b> "+license+"</div>";
+            }
 
             fdiv.innerHTML = html;
     }
diff --git a/cog/templatetags/cog_utils.py b/cog/templatetags/cog_utils.py
index a9c2d6180..5fed2dcb1 100644
--- a/cog/templatetags/cog_utils.py
+++ b/cog/templatetags/cog_utils.py
@@ -4,10 +4,9 @@
 from cog.views import encodeMembershipPar, NEW_MEMBERSHIP, OLD_MEMBERSHIP, NO_MEMBERSHIP
 from cog.views import userCanPost, userCanView
 from django import template
-from django.core.urlresolvers import reverse
 from django.utils.html import conditional_escape
 from django.utils.safestring import mark_safe
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 import re
 from cog.utils import smart_truncate, INVALID_CHARS
 from cog.models.utils import get_project_communication_means
@@ -18,7 +17,7 @@
 from cog.util.thumbnails import getThumbnailPath
 from django.contrib.auth.models import AnonymousUser
 from django.core.exceptions import ObjectDoesNotExist
-import urlparse
+import urllib.parse
 import string
 import bleach
 from cog.views.utils import getKnownIdentityProviders, getQueryDict, paginate
@@ -31,13 +30,13 @@ def wps_arguments(the_dict):
 
     for f in settings.WPS_FIELDS:
         if f in the_dict:
-	    args[f] = the_dict[f]
+	        args[f] = the_dict[f]
 
     return args
 
 @register.filter
 def knownIdentityProviders(request):
-    return getKnownIdentityProviders().items()
+    return list(getKnownIdentityProviders().items())
 
 
 @register.filter
@@ -48,7 +47,7 @@ def concat(astring, bstring):
 @register.filter
 def sortdict(the_dict):
     tuples = []
-    for key, value in the_dict.iteritems():
+    for key, value in the_dict.items():
         tuples.append((key, value))
     return sorted(tuples, key=lambda tuple: tuple[0])
 
@@ -178,7 +177,7 @@ def _folder_tree(folder, user, esc, expanded=False, icon='folder'):
         #   its child folders in reverse order to keep the most recent folder on top.
         # closing upper-level child folders by default (e.g. folders under Presentations)
 
-        years = reversed(range(2000, 2025))  # create list of reversed integers representing years
+        years = reversed(list(range(2000, 2025)))  # create list of reversed integers representing years
         years_str = [str(_year) for _year in years]  # convert that list to a list of strings
 
         if folder.name == "Bookmarks":
@@ -776,7 +775,7 @@ def get_domain(url):
     Returns the domain part of a URL
     """
     
-    return urlparse.urlparse(url)[1]
+    return urllib.parse.urlparse(url)[1]
 
 @register.filter
 def get_target_url_with_next_url(request, target_url_name):
@@ -884,7 +883,7 @@ def getDisplayStatus(flag1, flag2):
     
 @register.filter
 def startsWith(text, starts):
-    if isinstance(text, basestring):
+    if isinstance(text, str):
         return text.starts_with(starts)
     return False
 
diff --git a/cog/templatetags/search_utils.py b/cog/templatetags/search_utils.py
index 8064f20e9..f8574adbd 100644
--- a/cog/templatetags/search_utils.py
+++ b/cog/templatetags/search_utils.py
@@ -1,7 +1,6 @@
 from django import template
 from cog.models.search import searchMappings
 from cog.site_manager import siteManager
-from string import replace
 import json
 from collections import OrderedDict
 from django.conf import settings
@@ -168,7 +167,7 @@ def qcflags(record):
             qcflags[qcflag_name][int(qcflag_order)] = qcflag_value
     # for each qcflag, sort dictionary of values by their key (i.e. by the QC flag value order)
     for key in qcflags:
-        qcflags[key] = OrderedDict(sorted(qcflags[key].items(), key=lambda t: t[0]))
+        qcflags[key] = OrderedDict(sorted(list(qcflags[key].items()), key=lambda t: t[0]))
             
     # note: to enable easy access in html template, return the sorted set of (key, value) pairs
     # where the value is itself an ordered dictionary
diff --git a/cog/tests.py b/cog/tests.py
index 2247054b3..c7c4668e1 100644
--- a/cog/tests.py
+++ b/cog/tests.py
@@ -12,7 +12,7 @@ def test_basic_addition(self):
         """
         Tests that 1 + 1 always equals 2.
         """
-        self.failUnlessEqual(1 + 1, 2)
+        self.assertEqual(1 + 1, 2)
 
 __test__ = {"doctest": """
 Another way to test that 1 + 1 is equal to 2.
diff --git a/cog/tests/test_openid.py b/cog/tests/test_openid.py
index 1a7862363..20b51aad9 100644
--- a/cog/tests/test_openid.py
+++ b/cog/tests/test_openid.py
@@ -6,7 +6,7 @@
 import os
 import sys
 import unittest
-import urllib2
+import urllib.request, urllib.error, urllib.parse
 
 # list of openids from different ESGF IdPs
 OPENIDS = ['https://pcmdi9.llnl.gov/esgf-idp/openid/lucacinquini',
@@ -55,10 +55,10 @@ def testValidOpenids(self):
         
         for openid in OPENIDS:
             try:
-                response = urllib2.urlopen(openid)
+                response = urllib.request.urlopen(openid)
                 self.assertEqual(response.getcode(), 200, 'Invalid openid: %s' % openid)
             except Exception as e:
-                print 'Invalid openid: %s' % openid
+                print('Invalid openid: %s' % openid)
                 raise e
 
 
diff --git a/cog/tests/test_registration.py b/cog/tests/test_registration.py
index 30d25576d..0521039a0 100644
--- a/cog/tests/test_registration.py
+++ b/cog/tests/test_registration.py
@@ -35,7 +35,7 @@ def tearDown(self):
 
     def testGroups(self):
         groups = self.registrationService.listGroups()
-        g = {'visible': True, 'automatic_approval': False, 'name': u'TestGroup', 'description': u'Description'}
+        g = {'visible': True, 'automatic_approval': False, 'name': 'TestGroup', 'description': 'Description'}
         self.assertIn(g, groups)
         
     def _testUserRegistration(self):
diff --git a/cog/urls.py b/cog/urls.py
index b696a1093..9736ba255 100644
--- a/cog/urls.py
+++ b/cog/urls.py
@@ -38,7 +38,7 @@
     # authentication options
     # a) django (username/password) login
     #url(r'^login/$', 'django.contrib.auth.views.login', {'template_name': 'cog/account/login.html'}, name='login'),
-    url(r'^login2/$', django.contrib.auth.views.login, {'template_name': 'cog/account/login.html'}, name='login'),
+    url(r'^login2/$', django.contrib.auth.views.LoginView.as_view(template_name='cog/account/login.html'), name='login'),
     
     # b) combined django + openid login
     #url(r'^login/$', custom_login, {'template_name': 'cog/openid/login2.html'}, name='login'),
@@ -57,7 +57,7 @@
     # force redirection to login page after logout
     #url(r'^logout/$', 'django.contrib.auth.views.logout_then_login', name='logout'),
     # use next=... to redirect to previous page after logout
-    url(r'^logout/$', django.contrib.auth.views.logout, name='logout'),
+    url(r'^logout/$', django.contrib.auth.views.LogoutView.as_view(), name='logout'),
 
     # user management
     url(r'^user/add/$', cog.views.user_add, name='user_add' ),
diff --git a/cog/util/thumbnails.py b/cog/util/thumbnails.py
index 42c24ddcb..061c41e6b 100644
--- a/cog/util/thumbnails.py
+++ b/cog/util/thumbnails.py
@@ -53,8 +53,8 @@ def generateThumbnail(filePath, thumbnail_size):
             im.thumbnail(thumbnail_size)
             im.save(thumbnailPath, "PNG")
         except IOError as error:
-            print "Cannot create thumbnail for %s, using full image instead " % filePath
-            print error
+            print("Cannot create thumbnail for %s, using full image instead " % filePath)
+            print(error)
             shutil.copy(filePath, thumbnailPath)
 
 def deleteThumbnail(filePath):
@@ -63,8 +63,8 @@ def deleteThumbnail(filePath):
         try:
             os.remove(thumbnailPath)
         except IOError as error:
-            print "Cannot delete thumbnail for", filePath
-            print error
+            print("Cannot delete thumbnail for", filePath)
+            print(error)
             
 def deleteImageAndThumbnail(obj):
     '''Method to delete an object image and thumbnail simultaneously.'''
diff --git a/cog/utils.py b/cog/utils.py
index 90d7474d0..717580169 100644
--- a/cog/utils.py
+++ b/cog/utils.py
@@ -2,7 +2,7 @@
 from django import forms
 import os
 import datetime
-import urllib2
+import urllib.request, urllib.error, urllib.parse
 import json
 
 # timeout for JSON HTTP requests
@@ -35,7 +35,7 @@ def clean_field(form, field, invalid_characters):
     #    raise forms.ValidationError("The field %s contains invalid characters" % field)
     for c in data:
         if re.match(invalid_characters, c):
-            print 'Invalid character: %s' % c
+            print('Invalid character: %s' % c)
             raise forms.ValidationError("The character '%s' is invalid." % c)
     return data
 
@@ -65,15 +65,15 @@ def getJson(url):
     '''Retrieves and parses a JSON document at some URL.'''
     
     try:
-        opener = urllib2.build_opener()
-        request = urllib2.Request(url)
+        opener = urllib.request.build_opener()
+        request = urllib.request.Request(url)
         response = opener.open(request, timeout=TIMEOUT)
         jdoc = response.read()
         return json.loads(jdoc)
         
     except Exception as e:
-        print e
-        print 'Error retrieving URL=%s' % url
+        print(e)
+        print('Error retrieving URL=%s' % url)
         return None
     
 def check_filepath(file_full_path, expected_file_names):
diff --git a/cog/views/__init__.py b/cog/views/__init__.py
index 6d8b34eb9..1d8de486c 100644
--- a/cog/views/__init__.py
+++ b/cog/views/__init__.py
@@ -1,22 +1,22 @@
 from cog.views.constants import *
-from views_templated import *
-from views_bookmarks import *
-from views_account import *
-from views_datacart import *
-from views_doc import *
-from views_external_urls import *
-from views_account import *
-from views_governance import *
-from views_admin import *
-from views_membership import *
-from views_news import *
-from views_post import *
-from views_project import *
-from views_signal import *
-from views_aboutus import *
-from views_search import *
+from .views_templated import *
+from .views_bookmarks import *
+from .views_account import *
+from .views_datacart import *
+from .views_doc import *
+from .views_external_urls import *
+from .views_account import *
+from .views_governance import *
+from .views_admin import *
+from .views_membership import *
+from .views_news import *
+from .views_post import *
+from .views_project import *
+from .views_signal import *
+from .views_aboutus import *
+from .views_search import *
 from cog.views.views_share import *
 from cog.views.views_access_control import *
 from cog.views.views_globus import *
 from cog.views.utils import *
-from views_status import *
\ No newline at end of file
+from cog.views.views_status import *
diff --git a/cog/views/utils.py b/cog/views/utils.py
index 05fbc5bc1..fa871ca5a 100644
--- a/cog/views/utils.py
+++ b/cog/views/utils.py
@@ -8,7 +8,7 @@
 from cog.models.peer_site import getPeerSites
 from django.contrib.sites.models import Site
 from django.core.exceptions import ObjectDoesNotExist
-import urllib
+import urllib.request, urllib.parse, urllib.error
 from collections import OrderedDict
 from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
 
@@ -68,7 +68,7 @@ def getProjectNotVisibleRedirect(request, project):
 def set_openid_cookie(response, openid):
     """Utility method to consistently set the openid cookie."""
     
-    print 'SETTING openid cookie to: %s' % openid
+    print('SETTING openid cookie to: %s' % openid)
     
     response.set_cookie('openid', openid, 
                         expires=(datetime.datetime.now() + datetime.timedelta(days=3650)),  # expires in 10 years
@@ -151,7 +151,7 @@ def get_all_shared_user_info(user, includeCurrentSite=True):
         if user.profile.openid() is not None:
             
             openid = user.profile.openid()
-            print 'Retrieving projects, groups for user with openid=%s' % openid
+            print('Retrieving projects, groups for user with openid=%s' % openid)
             
             # loop over remote (enabled) nodes, possibly add current node
             sites = list(getPeerSites())
@@ -161,12 +161,12 @@ def get_all_shared_user_info(user, includeCurrentSite=True):
             for site in sites:
                             
                 url = "http://%s/share/user/?openid=%s" % (site.domain, openid)
-                print 'Retrieving user projects and groups from URL=%s' % url
+                print('Retrieving user projects and groups from URL=%s' % url)
                 jobj = getJson(url)
                 if jobj is not None and openid in jobj['users']:
                     userDict[site] = jobj['users'][openid] 
                 else:
-                    print 'Openid=%s not found at site=%s' % (openid, site)
+                    print('Openid=%s not found at site=%s' % (openid, site))
                                                             
     except UserProfile.DoesNotExist:
         pass  # user profile not yet created
@@ -174,18 +174,18 @@ def get_all_shared_user_info(user, includeCurrentSite=True):
     # restructure information as list of (project object, user roles) and (group name, group roles) tuples
     projects = []
     groups = []
-    for usite, udict in userDict.items():
+    for usite, udict in list(userDict.items()):
         if udict.get('projects', None):
-            for pname, proles in udict["projects"].items():
+            for pname, proles in list(udict["projects"].items()):
                 try:
                     proj = Project.objects.get(short_name__iexact=pname)
                     projects.append((proj, proles))
                 except ObjectDoesNotExist:
                     pass
         if udict.get('groups', None):
-            for gname, gdict in udict["groups"].items():
+            for gname, gdict in list(udict["groups"].items()):
                 groles = []
-                for grole, approved in gdict.items():
+                for grole, approved in list(gdict.items()):
                     if approved:
                         groles.append(grole)
                 groups.append((gname,groles))
@@ -199,9 +199,9 @@ def add_get_parameter(url, key, value):
     """
     
     if '?' in url:
-        return url + "&%s" % urllib.urlencode([(key, value)])
+        return url + "&%s" % urllib.parse.urlencode([(key, value)])
     else:
-        return url + "?%s" % urllib.urlencode([(key, value)])
+        return url + "?%s" % urllib.parse.urlencode([(key, value)])
     
 def getQueryDict(request):
     '''Utiity method to return the query dictionary for a GET or POST request.'''
diff --git a/cog/views/views_aboutus.py b/cog/views/views_aboutus.py
index 65e32716d..a7fca44ce 100644
--- a/cog/views/views_aboutus.py
+++ b/cog/views/views_aboutus.py
@@ -1,7 +1,7 @@
 from django.shortcuts import get_object_or_404, render, redirect
 from django.template import RequestContext
 from django.http import HttpResponseRedirect, HttpResponseForbidden
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.contrib.auth.decorators import login_required, user_passes_test, permission_required
 from django.forms.models import modelformset_factory, inlineformset_factory
 import string
@@ -20,7 +20,7 @@
 from cog.util.thumbnails import *
 from cog.models.auth import userHasAdminPermission
 
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 
 
 def aboutus_display(request, project_short_name, tab):
@@ -95,7 +95,7 @@ def aboutus_update(request, project_short_name, tab):
         else:
             # re-display form view
             if not form.is_valid():
-                print 'Form is invalid  %s' % form.errors
+                print('Form is invalid  %s' % form.errors)
             return render_aboutus_form(request, project, tab, form)
 
 
@@ -159,7 +159,7 @@ def impacts_update(request, project_short_name, tab):
             return HttpResponseRedirect(redirect)
 
         else:
-            print formset.errors
+            print(formset.errors)
             return render_impacts_form(request, project, formset, tab)
 
 
@@ -276,11 +276,11 @@ def _imageformset_update(request, project, tab,
                             deleteImageAndThumbnail(form.instance)
 
                 except ValueError as error:
-                    print error
+                    print(error)
                     
                 # delete object
                 if form.cleaned_data.get('DELETE', False):
-                    print 'Deleting instance=%s' % form.instance
+                    print('Deleting instance=%s' % form.instance)
                     form.instance.delete()
 
             # persist formset data
@@ -310,14 +310,14 @@ def _imageformset_update(request, project, tab,
                     try:
                         generateThumbnail(instance.image.path, thumbnail_size)
                     except ValueError as e:
-                        print e
+                        print(e)
                         pass  # no image supplied
 
             # redirect to people display (GET-POST-REDIRECT)
             return HttpResponseRedirect(reverse('aboutus_display', args=[project.short_name.lower(), tab]))
 
         else:
-            print 'Formset is invalid  %s' % formset.errors
+            print('Formset is invalid  %s' % formset.errors)
             return render_formset(form_template, request, project, tab, formset)
 
 
diff --git a/cog/views/views_access_control.py b/cog/views/views_access_control.py
index 87d79f91d..16cf5020c 100644
--- a/cog/views/views_access_control.py
+++ b/cog/views/views_access_control.py
@@ -7,8 +7,7 @@
 
 from django.contrib.auth.decorators import login_required
 from django.contrib.sites.models import Site
-from django.core.urlresolvers import reverse
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.http import HttpRequest, HttpResponseForbidden, HttpResponseRedirect
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
@@ -24,7 +23,7 @@
 from cog.plugins.esgf.objects import ROLE_USER, ROLE_PUBLISHER, ROLE_SUPERUSER, ROLE_ADMIN
 from cog.services.registration import esgfRegistrationServiceImpl as registrationService
 from cog.utils import getJson
-from constants import PERMISSION_DENIED_MESSAGE, SAVED, GROUP_NOT_FOUND_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE, SAVED, GROUP_NOT_FOUND_MESSAGE
 from cog.plugins.esgf.security import esgfDatabaseManager
 
 
@@ -55,7 +54,7 @@ def ac_subscribe(request, group_name):
             status = registrationService.status(request.user.profile.openid(), group_name, ROLE_USER)
         except ObjectDoesNotExist:
             # user does not exist in ESGF database
-            print 'Inserting user into ESGF security database'
+            print('Inserting user into ESGF security database')
             esgfDatabaseManager.insertEsgfUser(request.user.profile)
             status = None
         
@@ -114,7 +113,7 @@ def ac_process(request, group_name, user_id):
         # set initial status of check boxes from database
         initial = {}
         permissions = registrationService.list(openid, group_name)
-        for role, approved in permissions.items():
+        for role, approved in list(permissions.items()):
             initial['%sPermissionCheckbox' % role] = approved
         
         form = PermissionForm(initial=initial)
@@ -150,7 +149,7 @@ def ac_process(request, group_name, user_id):
                                         + "?message=%s" % SAVED)
             
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render(request, template, 
                           {'group_name': group_name, 'title': title, 'user': user, 'form': form})
 
@@ -173,7 +172,7 @@ def ac_list(request):
             site_domain = jobj['site']['domain']
 
             # loop over groups for this node
-            for group_name, group_dict in jobj['groups'].items():
+            for group_name, group_dict in list(jobj['groups'].items()):
                 # augment group dictionary
                 group_dict['site_name'] = site_name
                 group_dict['site_domain'] = site_domain
@@ -227,7 +226,7 @@ def notifyUser(group_name, user, permissions):
     subject = "'%s' Data Access Notification" % group_name
     message = "Your permissions in group '%s' have been updated" % group_name
     
-    for (role, status) in permissions.items():
+    for (role, status) in list(permissions.items()):
         message += "\nRole: %s status=%s" % (role, status)
         
     notify(user, subject, message)
diff --git a/cog/views/views_account.py b/cog/views/views_account.py
index 3ab5e00c2..0ee283ca7 100644
--- a/cog/views/views_account.py
+++ b/cog/views/views_account.py
@@ -1,13 +1,13 @@
-import urllib
-from urlparse import urlparse
+import urllib.request, urllib.parse, urllib.error
+from urllib.parse import urlparse
 
 from django.contrib.auth import logout
 from django.contrib.auth.decorators import login_required, user_passes_test
 from django.contrib.auth.hashers import is_password_usable
-from django.contrib.auth.views import login
+from django.contrib.auth.views import LoginView
 from django.contrib.sites.models import Site
 from django.core.exceptions import ObjectDoesNotExist
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.forms.models import modelformset_factory
 from django.http import HttpResponseRedirect, HttpResponseNotAllowed, HttpResponseServerError
 from django.shortcuts import get_object_or_404, render
@@ -43,7 +43,7 @@ def custom_login(request, **kwargs):
     """
     
     # authenticate user via standard login
-    response = login(request, **kwargs)
+    response = LoginView.as_view(**kwargs)(request)
 
     # check if user is valid
     return _custom_login(request, response)
@@ -59,14 +59,14 @@ def custom_login_complete(request, **kwargs):
     response = login_complete(request, **kwargs)
 
     # create a stub profile with blank mandatory fields
-    if not request.user.is_anonymous():
+    if not request.user.is_anonymous:
         openid = request.GET.get('openid.claimed_id', None)
         try:
             request.user.profile
             
         except ObjectDoesNotExist:
 
-            print 'Discovering site for user with openid=%s' % openid
+            print('Discovering site for user with openid=%s' % openid)
             
             # retrieve user home node
             site = discoverSiteForUser(openid)
@@ -74,7 +74,7 @@ def custom_login_complete(request, **kwargs):
                 # set user home node to current node
                 site = Site.objects.get_current()
                 
-            print 'User site=%s... creating user profile...' % site
+            print('User site=%s... creating user profile...' % site)
                 
             # create new ESGF/OpenID login, type=2: ESGF
             UserProfile.objects.create(user=request.user, institution='', city='', country='', type=2, site=site)
@@ -92,11 +92,11 @@ def custom_login_complete(request, **kwargs):
 def _custom_login(request, response):
     
     # successful login
-    if not request.user.is_anonymous():
+    if not request.user.is_anonymous:
                 
         # missing information
         if isUserLocal(request.user) and not isUserValid(request.user):
-            print 'User is local but some information is missing, redirecting to user update page'
+            print('User is local but some information is missing, redirecting to user update page')
             return HttpResponseRedirect(reverse('user_update', kwargs={'user_id': request.user.id}) +
                                         "?message=incomplete_profile")
         
@@ -180,7 +180,7 @@ def _sendSubsriptionEmail(user, action):
     # body
     message = ''
     
-    print 'Sending subscription email: To=%s Subject=%s' % (toAddress, subject)
+    print('Sending subscription email: To=%s Subject=%s' % (toAddress, subject))
     sendEmail(toAddress, subject, message, fromAddress=user.email)
 
 
@@ -188,14 +188,15 @@ def _sendSubsriptionEmail(user, action):
 def user_add(request):
     
     # redirection URL
-    _next = request.GET.get('next', None) or request.POST.get('next', None)
-    
+#    _next = request.GET.get('next', None) or request.POST.get('next', None)
+    _next = None
+
     # redirect to another node if necessary
     if redirectToIdp():
         redirect_url = settings.IDP_REDIRECT + request.path
         if _next is not None:
-            redirect_url += ("?next=%s" % urllib.quote_plus(_next))
-        print 'Redirecting account creation to: %s' % redirect_url
+            redirect_url += ("?next=%s" % urllib.parse.quote_plus(_next))
+        print('Redirecting account creation to: %s' % redirect_url)
         return HttpResponseRedirect(redirect_url)
 
     # create URLs formset
@@ -226,14 +227,14 @@ def user_add(request):
                         
             # save user to database
             user.save()
-            print 'Created user=%s' % user.username
+            print('Created user=%s' % user.username)
             
             # create openid
             if settings.ESGF_CONFIG:
                 openid = form.cleaned_data['openid']
-                print 'Creating openid=%s' % openid
+                print('Creating openid=%s' % openid)
                 userOpenID = UserOpenID.objects.create(user=user, claimed_id=openid, display_id=openid)
-                print 'Added openid=%s for user=%s into COG database' % (openid, user.username)
+                print('Added openid=%s for user=%s into COG database' % (openid, user.username))
 
             # use additional form fields to create user profile
             userp = UserProfile(user=user,
@@ -287,39 +288,40 @@ def user_add(request):
             # redirect to login page with special message
             login_url = reverse('login')+"?message=user_add"
             if _next is not None and len(_next.strip()) > 0:
-                login_url += ("&next=%s" % urllib.quote_plus(_next))
+                login_url += ("&next=%s" % urllib.parse.quote_plus(_next))
                 # redirect to absolute URL (possibly at an another node)
                 if 'http' in _next:
                     url = urlparse(_next)
                     login_url = '%s://%s%s' % (url.scheme, url.netloc, login_url)
             # append openid to initial login_url
             if userp.openid() is not None:
-                login_url += "&openid=%s" % urllib.quote_plus(userp.openid())
-            login_url += "&username=%s" % urllib.quote_plus(userp.user.username)
+                login_url += "&openid=%s" % urllib.parse.quote_plus(userp.openid())
+            login_url += "&username=%s" % urllib.parse.quote_plus(userp.user.username)
             
             response = HttpResponseRedirect(login_url)
             
             # set openid cookie on this host
             set_openid_cookie(response, userp.openid())
 
-            print 'New user account created: redirecting to login url: %s' % login_url
+            print('New user account created: redirecting to login url: %s' % login_url)
             return response
 
         else:
             if not form.is_valid():
-                print "Form is invalid: %s" % form.errors
+                print("Form is invalid: %s" % form.errors)
             elif not formset.is_valid():
-                print "URL formset is invalid: %s" % formset.errors
+                print("URL formset is invalid: %s" % formset.errors)
             return render_user_form(request, form, formset, title='Create User Profile')
 
 
 # view to display user data
 # require login to limit exposure of user information
-#@login_required
+@login_required
 def user_detail(request, user_id):
 
     # load User object
     user = get_object_or_404(User, pk=user_id)
+
     # try loading user profile
     try:
         user_profile = UserProfile.objects.get(user=user)
@@ -327,16 +329,20 @@ def user_detail(request, user_id):
     except:
         user_profile = UserProfile(user=user)
         user_profile.save()
-        print "Created empty profile for user=%s" % user
+        print("Created empty profile for user=%s" % user)
         
     # retrieve map of (project, roles) for this user
     (projTuples, groupTuples) = get_all_shared_user_info(user)
-    print "\nprojTuples="
-    print projTuples
+    print("\nprojTuples=")
+    print(projTuples)
         
     # sort projects, groups alphabetically
     projects = sorted(projTuples, key=lambda x: x[0].short_name)
     groups = sorted(groupTuples, key=lambda x: x[0])
+
+    if user != request.user and not request.user.is_staff:
+        return HttpResponseServerError("Not authorized to access another user's profile..")
+
             
     return render(request, 'cog/account/user_detail.html',
                   {'user_profile': user_profile, 'projects': projects, 'groups':groups, 'title': 'User Profile'})
@@ -443,7 +449,8 @@ def user_update(request, user_id):
 
     # security check
     if str(request.user.id) != user_id and not request.user.is_staff:
-        raise Exception("User not authorized to change profile data")
+        return HttpResponseServerError("Not authorized to update another user's profile..")
+
 
     # get user
     user = get_object_or_404(User, pk=user_id)
@@ -486,7 +493,7 @@ def user_update(request, user_id):
             # delete UserUrls if found
             urls = UserUrl.objects.filter(profile=profile)
             for url in urls:
-                print 'Deleting user URL: %s' % url.url
+                print('Deleting user URL: %s' % url.url)
                 url.delete()
 
             # update user
@@ -515,7 +522,7 @@ def user_update(request, user_id):
             if not is_password_usable(user.password):
                 user.set_password(form.cleaned_data['password'])
                 user.save()
-                print 'Reset password for user=%s' % user
+                print('Reset password for user=%s' % user)
 
             # image management
             _generateThumbnail = False
@@ -571,9 +578,9 @@ def user_update(request, user_id):
 
         else:
             if not form.is_valid():
-                print "Form is invalid: %s" % form.errors
+                print("Form is invalid: %s" % form.errors)
             elif not formset.is_valid():
-                print "URL formset is invalid: %s" % formset.errors
+                print("URL formset is invalid: %s" % formset.errors)
                 
             return render_user_form(request, form, formset, title='Update User Profile')
 
@@ -639,7 +646,7 @@ def password_update(request, user_id):
                                                     kwargs={'user_id': user.id})+"?message=password_updated_by_admin")
 
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render_password_change_form(request, form, user.username)
 
 
@@ -684,7 +691,7 @@ def user_reminder(request):
                 return render_user_reminder_form(request, form, "This email address cannot be found.")
 
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render_user_reminder_form(request, form)
 
 
@@ -708,7 +715,7 @@ def password_reset(request):
 
         # check form is valid first
         if not form.is_valid():
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render_password_reset_form(request, form)
 
         openid = form.cleaned_data.get('openid')
@@ -820,4 +827,4 @@ def render_user_reminder_form(request, form, message=""):
 
 def render_site_change_form(request, form):
     return render(request, 'cog/account/site_change.html',
-                              {'form': form, 'mytitle' : 'Change User Home Node' })
\ No newline at end of file
+                              {'form': form, 'mytitle' : 'Change User Home Node' })
diff --git a/cog/views/views_admin.py b/cog/views/views_admin.py
index af29d0f44..d5819e86c 100644
--- a/cog/views/views_admin.py
+++ b/cog/views/views_admin.py
@@ -1,7 +1,7 @@
 from cog.forms import *
 from cog.models import *
 from django.contrib.auth.decorators import login_required, user_passes_test
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.http import HttpResponseRedirect
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
@@ -97,6 +97,6 @@ def admin_peers(request):
             return HttpResponseRedirect(reverse('admin_peers')+"?status=success")
         
         else:
-            print formset.errors
+            print(formset.errors)
             return render(request,
                           'cog/admin/admin_peers.html', {'formset': formset})
\ No newline at end of file
diff --git a/cog/views/views_bookmarks.py b/cog/views/views_bookmarks.py
index 0e740df57..64fe65f7e 100644
--- a/cog/views/views_bookmarks.py
+++ b/cog/views/views_bookmarks.py
@@ -7,9 +7,9 @@
 from django.http import HttpResponseRedirect, HttpResponseForbidden
 import json
 from django.http import HttpResponse  
-from constants import PERMISSION_DENIED_MESSAGE, BAD_REQUEST
-from utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
-from views_post import post_add
+from .constants import PERMISSION_DENIED_MESSAGE, BAD_REQUEST
+from .utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
+from .views_post import post_add
 from cog.models.auth import userHasContributorPermission
 
 
@@ -102,7 +102,7 @@ def bookmark_add(request, project_short_name):
             return HttpResponseRedirect(reverse('bookmark_list', args=[project.short_name.lower()]))
                           
         else:
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
             return render_bookmark_form(request, project, form) 
 
 
@@ -132,9 +132,9 @@ def bookmark_add2(request, project_short_name):
             response_data['message'] = 'Your bookmark was saved.'
                                       
         else:
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
             # encode errors in response - although not used
-            for key, value in form.errors.items():
+            for key, value in list(form.errors.items()):
                 response_data['errors'][key] = value           
             response_data['result'] = 'Error'
             response_data['message'] = 'Sorry, the form data is invalid: %s' % form.errors
@@ -198,7 +198,7 @@ def bookmark_update(request, project_short_name, bookmark_id):
             # update associated Doc, if any
             doc = getDocFromBookmark(bookmark)
             if doc is not None:
-                print 'Updating associated doc: %s' % doc
+                print('Updating associated doc: %s' % doc)
                 doc.title = bookmark.name
                 doc.description = bookmark.description
                 doc.save()
@@ -207,7 +207,7 @@ def bookmark_update(request, project_short_name, bookmark_id):
             return HttpResponseRedirect(reverse('bookmark_list', args=[project.short_name.lower()]))
             
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             # return to view
             return render_bookmark_form(request, project, form)  
     
@@ -261,7 +261,7 @@ def folder_add(request, project_short_name):
             
         else:
             # return to view
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render_folder_form(request, project, form) 
 
 
@@ -295,7 +295,7 @@ def folder_update(request, project_short_name, folder_id):
             
         else:
             # return to view
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             return render_folder_form(request, folder.project, form) 
 
 
@@ -331,11 +331,11 @@ def delete_folder(folder):
     
     # delete folder bookmarks
     for bookmark in folder.bookmark_set.all():
-        print 'Deleting bookmark=%s' % bookmark
+        print('Deleting bookmark=%s' % bookmark)
         bookmark.delete()
 
     # delete this folder
-    print 'Deleting folder=%s' % folder
+    print('Deleting folder=%s' % folder)
     folder.delete()
 
 
diff --git a/cog/views/views_datacart.py b/cog/views/views_datacart.py
index 3db59548b..6b3d41d4d 100644
--- a/cog/views/views_datacart.py
+++ b/cog/views/views_datacart.py
@@ -1,7 +1,9 @@
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
+from django.conf import settings
+from urllib.parse import urlparse
 from django.http import HttpResponseRedirect, HttpResponse, HttpResponseForbidden, HttpResponseNotAllowed
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from cog.models import *
 from django.contrib.auth.decorators import login_required
 import re
@@ -36,7 +38,6 @@ def datacart_display(request, site_id, user_id):
         datacart = DataCart.objects.get(user=user)
     except DataCart.DoesNotExist:
         datacart = None
-
     return render(request,
                   'cog/datacart/datacart.html', 
                   {'datacart': datacart})    
@@ -124,15 +125,15 @@ def datacart_add_all(request, site_id, user_id):
         searchOutput = data[SEARCH_OUTPUT]
         
         # loop over record
-        print "Adding %s items" % len(searchOutput.results)
+        print("Adding %s items" % len(searchOutput.results))
         for record in searchOutput.results:
             
             # check item is not in cart already
             if DataCartItem.objects.filter(cart=datacart, identifier=record.id).exists():
-                print 'Item %s already in Data Cart' % record.id
+                print('Item %s already in Data Cart' % record.id)
             else:
                 item = DataCartItem.fromRecord(datacart, record)
-                print 'Added item: %s' % record.id
+                print('Added item: %s' % record.id)
 
     # redirect to search results
     back = request.GET.get('back', '/')
@@ -162,12 +163,12 @@ def datacart_delete_all(request, site_id, user_id):
         searchOutput = data[SEARCH_OUTPUT]
         
         # loop over record
-        print "Deleting %s items" % len(searchOutput.results)
+        print("Deleting %s items" % len(searchOutput.results))
         for record in searchOutput.results:
             
             try:
                 item = DataCartItem.objects.get(cart=datacart, identifier=record.id)
-                print 'Deleting item: %s' % item.id
+                print('Deleting item: %s' % item.id)
                 item.delete()
             except ObjectDoesNotExist:
                 pass
@@ -355,6 +356,6 @@ def datacart_pid(request, site_id, user_id):
     pid = connector.create_data_cart_pid(dataset_ids)
     connector.finish_messaging_thread()
 
-    print 'Generated data cart PID for %d datasets: %s' % (len(ids), pid)
+    print('Generated data cart PID for %d datasets: %s' % (len(ids), pid))
 
     return HttpResponse(json.dumps(pid), content_type="application/json")
diff --git a/cog/views/views_doc.py b/cog/views/views_doc.py
index 67554356d..107a90d58 100644
--- a/cog/views/views_doc.py
+++ b/cog/views/views_doc.py
@@ -2,10 +2,10 @@
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
 from django.http import HttpResponseRedirect, HttpResponseForbidden
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from cog.models import *
 from cog.forms import *
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 from os.path import basename
 from django.views.decorators.csrf import csrf_exempt
 from cog.forms import UploadImageForm
@@ -46,7 +46,7 @@ def doc_upload(request, project_short_name):
             error = ''
             
         else:
-            print 'Form errors:%s' % form.errors
+            print('Form errors:%s' % form.errors)
             error = 'The file uploaded is not an image. Valid files include PNG, JPG, and PDF.'
             url = "%s%s" % (settings.STATIC_URL, 'cog/img/error.jpeg')
     
@@ -155,7 +155,7 @@ def data_download(request, path):
     
     project_short_name = path.split("/")[0]
     project = get_object_or_404(Project, short_name__iexact=project_short_name)
-    print 'Data for project=%s' % project
+    print('Data for project=%s' % project)
     
     # TODO: check if data is public before forcing login
     return secure_data_download(request, path, project)
@@ -235,7 +235,7 @@ def doc_update(request, doc_id):
                 bookmark.name = doc.title
                 bookmark.description = doc.description
                 bookmark.save()
-                print 'Updated associated bookmark: %s' % bookmark
+                print('Updated associated bookmark: %s' % bookmark)
             
             # redirect to document detail (GET-POST-REDIRECT)
             return HttpResponseRedirect(reverse('doc_detail', kwargs={'doc_id': doc.id}))
@@ -253,7 +253,7 @@ def doc_list(request, project_short_name):
     #list_title = 'All Documents'
     
     # do not list private documents unless user is a project member
-    if request.user.is_anonymous() or not userHasUserPermission(request.user, project):
+    if request.user.is_anonymous or not userHasUserPermission(request.user, project):
         qset = qset & Q(is_private=False)
     
     # optional query parameters
diff --git a/cog/views/views_external_urls.py b/cog/views/views_external_urls.py
index e388b7718..298d1445e 100644
--- a/cog/views/views_external_urls.py
+++ b/cog/views/views_external_urls.py
@@ -5,12 +5,12 @@
 from django.contrib.auth.decorators import login_required
 from cog.forms import *
 from django.http import HttpResponseRedirect
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.http import HttpResponse, HttpResponseForbidden
 from django.forms.models import modelformset_factory
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 from cog.models.constants import *
-from utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
+from .utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
 from cog.models.navbar import TABS
 from cog.models.external_url_conf import externalUrlManager
 from cog.models.auth import userHasContributorPermission
@@ -107,7 +107,7 @@ def external_urls_update(request, project_short_name, suburl):
     
     # GET
     if request.method == 'GET':
-        print type
+        print(type)
 
         # create formset instance backed by current saved instances
         # must provide the initial data to all the extra instances, 
@@ -148,7 +148,7 @@ def external_urls_update(request, project_short_name, suburl):
             return HttpResponseRedirect(redirect)
         
         else:
-            print formset.errors
+            print(formset.errors)
             return render_external_urls_form(request, project, formset, externalUrlConf, redirect)
 
 
diff --git a/cog/views/views_globus.py b/cog/views/views_globus.py
index 7bba1c000..928804348 100644
--- a/cog/views/views_globus.py
+++ b/cog/views/views_globus.py
@@ -1,15 +1,16 @@
-from django.core.urlresolvers import reverse
+from django.conf import settings
+from django.urls import reverse
 from django.contrib.auth.decorators import login_required
 from django.http import HttpResponse, HttpResponseRedirect, HttpResponseForbidden, HttpResponseServerError
 from django.shortcuts import render
 from django.template import RequestContext
-import urllib
+import urllib.request, urllib.parse, urllib.error
 from cog.utils import getJson
-from urlparse import urlparse
+from urllib.parse import urlparse
 from cog.constants import SECTION_GLOBUS
 from cog.site_manager import siteManager
 import datetime
-from constants import GLOBUS_NOT_ENABLED_MESSAGE
+from .constants import GLOBUS_NOT_ENABLED_MESSAGE
 from functools import wraps
 import os
 import re
@@ -40,7 +41,8 @@
 	from base64 import urlsafe_b64encode
 	from oauth2client import client as oauth_client
 	from cog.plugins.globus.transfer import activateEndpoint, submitTransfer, generateGlobusDownloadScript
-	from globusonline.transfer.api_client import TransferAPIClient
+	from globus_sdk.transfer import TransferClient
+	from globus_sdk import AccessTokenAuthorizer
 
 	client_id = siteManager.get('OAUTH_CLIENT_ID', section=SECTION_GLOBUS)
 	client_secret = siteManager.get('OAUTH_CLIENT_SECRET', section=SECTION_GLOBUS)
@@ -59,8 +61,8 @@ def discover_myproxy(openid):
 
 
 def establishFlow(request):
-	basic_auth_str = urlsafe_b64encode("{}:{}".format(client_id, client_secret))
-	auth_header = "Basic " + basic_auth_str
+	basic_auth_str = urlsafe_b64encode('{}:{}'.format(client_id, client_secret).encode())
+	auth_header = b'Basic ' + basic_auth_str
 	return oauth_client.OAuth2WebServerFlow(
 		client_id = client_id,
 		authorization_header = auth_header,
@@ -127,8 +129,8 @@ def download(request):
 			params.append(("distrib", "false"))
 
 			
-		url = "http://"+index_node+"/esg-search/search?"+urllib.urlencode(params)
-		print 'Searching for files at URL: %s' % url
+		url = "http://"+index_node+"/esg-search/search?"+urllib.parse.urlencode(params)
+		print('Searching for files at URL: %s' % url)
 		jobj = getJson(url)
 		
 		# parse response for GridFTP URls
@@ -152,13 +154,13 @@ def download(request):
 							download_map[gendpoint_name] = [] # insert empty list of paths
 						download_map[gendpoint_name].append(path)
 				else:
-					print 'The file is not accessible through Globus'
+					print('The file is not accessible through Globus')
 		else:
 			return HttpResponseServerError("Error querying for files URL")
 						
 	# store map in session
 	request.session[GLOBUS_DOWNLOAD_MAP] = download_map
-	print 'Stored Globus Download Map=%s at session scope' % download_map
+	print('Stored Globus Download Map=%s at session scope' % download_map)
 	
 	# redirect after post (to display page)
 	return HttpResponseRedirect( reverse('globus_transfer') )
@@ -185,8 +187,8 @@ def transfer(request):
 				   # ('lock', 'ep'), # do NOT allow the user to change their endpoint
 				   ('action', request.build_absolute_uri(reverse("globus_oauth")) ), # redirect to CoG Oauth URL
 				 ]
-		globus_url = GLOBUS_SELECT_DESTINATION_URL + "?" + urllib.urlencode(params)
-		print "Redirecting to: %s" % globus_url
+		globus_url = GLOBUS_SELECT_DESTINATION_URL + "?" + urllib.parse.urlencode(params)
+		print("Redirecting to: %s" % globus_url)
 		return HttpResponseRedirect(globus_url)
 		# replacement URL for localhost development
 		#return HttpResponseRedirect( request.build_absolute_uri(reverse("globus_oauth")) ) # FIXME
@@ -201,11 +203,11 @@ def oauth(request):
 	# /globus/oauth/?label=&verify_checksum=on&submitForm=&folder[0]=tmp&endpoint=cinquiniluca#mymac&path=/~/&ep=GC&lock=ep&method=get&folderlimit=1&action=http://localhost:8000/globus/oauth/
 	request.session[TARGET_ENDPOINT] = getQueryDict(request).get('endpoint','#')
 	request.session[TARGET_FOLDER] = getQueryDict(request).get('path','/~/') + getQueryDict(request).get('folder[0]', '')  # default value: user home directory
-	print 'User selected destionation endpoint:%s, path:%s, folder:%s' % (request.session[TARGET_ENDPOINT], getQueryDict(request).get('path','/~/'), getQueryDict(request).get('folder[0]', ''))
+	print('User selected destionation endpoint:%s, path:%s, folder:%s' % (request.session[TARGET_ENDPOINT], getQueryDict(request).get('path','/~/'), getQueryDict(request).get('folder[0]', '')))
 
 	# Redirect the user to Globus OAuth server to get an authorization code if the user approves the access request.
 	globus_authorize_url = establishFlow(request).step1_get_authorize_url()
-	print "Redirecting to: %s" % globus_authorize_url
+	print("Redirecting to: %s" % globus_authorize_url)
 	return HttpResponseRedirect(globus_authorize_url)
 
 
@@ -261,29 +263,26 @@ def submit(request):
 	target_folder = request.session.get(TARGET_FOLDER)
 
 	#print 'Downloading files=%s' % download_map.items()
-	print 'User selected destionation endpoint:%s, folder: %s' % (target_endpoint, target_folder)
+	print('User selected destionation endpoint:%s, folder: %s' % (target_endpoint, target_folder))
 
-	api_client = TransferAPIClient(username, goauth=access_token)
+	token_authorizer = AccessTokenAuthorizer(access_token)
+	transfer_client = TransferClient(token_authorizer)
 	# loop over source endpoints and autoactivate them
 	# if the autoactivation fails, redirect to a form asking for a password
-	activateEndpoint(api_client, target_endpoint)
+	activateEndpoint(transfer_client, target_endpoint)
 	for source_endpoint, source_files in download_map.items():
-		status, message = activateEndpoint(
-			api_client, source_endpoint,
-			myproxy_server=myproxy_server, username=esgf_username, password=esgf_password)
+		status, message = activateEndpoint(transfer_client, source_endpoint, myproxy_server=myproxy_server, username=esgf_username, password=esgf_password)
 		if not status:
-                        print hostname
-			return render(request,
-                          'cog/globus/password.html',
-                          { 'openid': openid, 'username': hostname=='ceda.ac.uk', 'message': message })
+			print(hostname)
+			return render(request, 'cog/globus/password.html', { 'openid': openid, 'username': hostname=='ceda.ac.uk', 'message': message })
 
 	# loop over source endpoints, submit one transfer for each source endpoint
 	task_ids = []  # list of submitted task ids
-	for source_endpoint, source_files in download_map.items():
+	for source_endpoint, source_files in list(download_map.items()):
 			
 		# submit transfer request
 		task_id = submitTransfer(
-			api_client, source_endpoint, source_files,
+			transfer_client, source_endpoint, source_files,
 			target_endpoint, target_folder)
 		task_ids.append(task_id)
 	
diff --git a/cog/views/views_governance.py b/cog/views/views_governance.py
index 3eebe14f7..251cd1b42 100644
--- a/cog/views/views_governance.py
+++ b/cog/views/views_governance.py
@@ -3,14 +3,14 @@
 from cog.models.constants import LEAD_ORGANIZATIONAL_ROLES_DICT, \
     ROLE_CATEGORY_LEAD, ROLE_CATEGORY_MEMBER, MANAGEMENT_BODY_CATEGORY_STRATEGIC, \
     MANAGEMENT_BODY_CATEGORY_OPERATIONAL
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 from django.contrib.auth.decorators import login_required
 from django.forms.models import BaseInlineFormSet, inlineformset_factory
 from django.http import HttpResponseRedirect, HttpResponse, HttpResponseForbidden
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
 from django.utils.functional import curry
-from utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
+from .utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
 from cog.models.navbar import TABS, TAB_LABELS
 from cog.views.views_templated import templated_page_display
 from cog.models.auth import userHasAdminPermission
@@ -120,7 +120,7 @@ def governance_overview_update(request, project_short_name):
             
         # return to form
         else:
-            print 'Form is invalid %s' % form.errors
+            print('Form is invalid %s' % form.errors)
             return render_governance_overview_form(request, form, project)
 
     
@@ -195,7 +195,7 @@ def governance_object_update(request, project_short_name, tab, objectType, objec
             return redirect
             
         else:
-            print 'Formset is invalid  %s' % formset.errors
+            print('Formset is invalid  %s' % formset.errors)
             return render_governance_object_form(request, project, formset, title, template)
             
 
@@ -291,7 +291,7 @@ def members_update(request, tab, objectId, objectType, objectMemberType, objectM
             return HttpResponseRedirect(redirect)
                       
         else:
-            print 'Formset is invalid: %s' % formset.errors
+            print('Formset is invalid: %s' % formset.errors)
             
             # redirect to form view
             return render_members_form(request, obj, formset, redirect)
@@ -343,7 +343,7 @@ def processes_update(request, project_short_name):
             
         # return to form
         else:
-            print 'Form is invalid %s' % form.errors
+            print('Form is invalid %s' % form.errors)
             return render_governance_processes_form(request, form, project)
 
 def render_governance_processes_form(request, form, project):
@@ -400,7 +400,7 @@ def organizational_role_update(request, project_short_name):
             return HttpResponseRedirect(reverse('governance_display', args=[project.short_name.lower(), tab]))
             
         else:
-            print 'Organizational Role formset is invalid: %s' % organizational_role_formset.errors
+            print('Organizational Role formset is invalid: %s' % organizational_role_formset.errors)
             
             # redorect to form
             return render_organizational_role_form(request, project, organizational_role_formset)
diff --git a/cog/views/views_membership.py b/cog/views/views_membership.py
index 49c998585..f26a01bff 100644
--- a/cog/views/views_membership.py
+++ b/cog/views/views_membership.py
@@ -4,7 +4,7 @@
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
 from django.http import HttpRequest, HttpResponseRedirect, HttpResponseForbidden
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.contrib.auth.decorators import login_required, user_passes_test, permission_required
 from cog.views.utils import getUsersThatMatch, getQueryDict
 from django.contrib.sites.models import Site
@@ -12,7 +12,7 @@
 from cog.views.utils import paginate
 
 from cog.notification import notify
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 
 # HTTP parameters
 NEW_MEMBERSHIP = "new_membership"
@@ -216,7 +216,7 @@ def membership_process(request, project_short_name):
 
     queryDict = getQueryDict(request)
     
-    for (name, value) in queryDict.items():
+    for (name, value) in list(queryDict.items()):
 
         if name.startswith(NEW_MEMBERSHIP) or name.startswith(OLD_MEMBERSHIP) or name.startswith(NO_MEMBERSHIP):
             (prefix, group_name, user_id) = name.split(":")
diff --git a/cog/views/views_news.py b/cog/views/views_news.py
index 10fb0fde9..01136a650 100644
--- a/cog/views/views_news.py
+++ b/cog/views/views_news.py
@@ -2,12 +2,12 @@
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
 from django.http import HttpResponseRedirect, HttpResponseForbidden
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 
 from cog.models import *
 from cog.models.auth import userHasContributorPermission
 from cog.forms import *
-from constants import PERMISSION_DENIED_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE
 from cog.views.utils import paginate
 
 
@@ -75,7 +75,7 @@ def news_update(request, news_id):
         
         # invalid data
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             news = form.instance
             return render_news_form(request, request.POST, form, news.project)
 
@@ -130,7 +130,7 @@ def news_add(request, project_short_name):
         
         # invalid data
         else:
-            print "Form is invalid: %s" % form.errors
+            print("Form is invalid: %s" % form.errors)
             news = form.instance
             return render_news_form(request, request.POST, form, news.project)
 
diff --git a/cog/views/views_post.py b/cog/views/views_post.py
index 94e2126d2..927093867 100644
--- a/cog/views/views_post.py
+++ b/cog/views/views_post.py
@@ -5,16 +5,16 @@
 from datetime import datetime
 from django.contrib.auth.decorators import login_required
 from django.core.exceptions import PermissionDenied
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.http import HttpResponseRedirect, Http404, HttpResponseForbidden
 from django.shortcuts import get_object_or_404, render
 from django.template import RequestContext
 from string import Template
-from urllib import quote, unquote
+from urllib.parse import quote, unquote
 import copy
-from constants import PERMISSION_DENIED_MESSAGE, LOCAL_PROJECTS_ONLY_MESSAGE
+from .constants import PERMISSION_DENIED_MESSAGE, LOCAL_PROJECTS_ONLY_MESSAGE
 from cog.models.constants import SIGNAL_OBJECT_CREATED, SIGNAL_OBJECT_UPDATED, SIGNAL_OBJECT_DELETED
-from utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
+from .utils import getProjectNotActiveRedirect, getProjectNotVisibleRedirect
 from django.utils.timezone import now
 from cog.models.utils import delete_doc
 from django.conf import settings
@@ -292,7 +292,7 @@ def post_add(request, project_short_name, owner=None):
                 
         # invalid data
         else:
-            print form.errors
+            print(form.errors)
             return render_post_form(request, form, project, postType)
 
 
@@ -382,7 +382,7 @@ def post_update(request, post_id):
         # check versions       
         queryDict = getQueryDict(request)
         if post.version != int(queryDict.get('version', -1)):
-            print 'database version=%s form version=%s' % (post.version, queryDict.get('version', -1))
+            print('database version=%s form version=%s' % (post.version, queryDict.get('version', -1)))
             return getLostLockRedirect(request, post.project, post, lock)
 
         #print "1 PAGE URL=%s" % form.data['url']
@@ -433,7 +433,7 @@ def post_update(request, post_id):
                     return HttpResponseRedirect(reverse('project_home', args=[post.project.short_name.lower()]))
 
         else:
-            print form.errors
+            print(form.errors)
             return render_post_form(request, form, post.project, post.type, lock=lock)
 
 
@@ -533,7 +533,7 @@ def getNotAuthorizedRedirect(request, post):
     
     # user is NOT authorized
     if not userCanView(request.user, post):
-        if not request.user.is_authenticated():
+        if not request.user.is_authenticated:
             return HttpResponseRedirect(reverse('login')+"?next=%s" % request.path)
         else:
             messages = ['This page is only viewable to members of %s.' % post.project.short_name,
diff --git a/cog/views/views_project.py b/cog/views/views_project.py
index 90f92637e..4c721dc77 100644
--- a/cog/views/views_project.py
+++ b/cog/views/views_project.py
@@ -96,7 +96,7 @@ def project_add(request):
         # invalid data
         else:
             
-            print "Form is invalid: %s" % form.errors           
+            print("Form is invalid: %s" % form.errors)           
             project = form.instance
             
             # create and set state of project tabs, do not persist
@@ -160,7 +160,7 @@ def project_index(request, project_short_name):
                 topicvalue = request.POST[topickey]
                 ii.order = topicvalue
                 # validate topic order
-                if topicvalue in topicMap.values():
+                if topicvalue in list(topicMap.values()):
                     valid = False
                     errors[topickey] = "Duplicate topic number: %d" % int(topicvalue)
                 else:
@@ -173,7 +173,7 @@ def project_index(request, project_short_name):
                 pagevalue = request.POST[pagekey]
                 page.order = pagevalue
                 # validate page order
-                if pagevalue in pageMap.values():
+                if pagevalue in list(pageMap.values()):
                     valid = False
                     errors[pagekey] = "Duplicate page number: %d" % int(pagevalue)
                 else:
@@ -271,7 +271,7 @@ def project_update(request, project_short_name):
             return HttpResponseRedirect(reverse('project_home', args=[project.short_name.lower()]))
 
         else:
-            print 'Form is invalid %s' % form.errors
+            print('Form is invalid %s' % form.errors)
             
             # update project tabs, but do not persist state since form had errors
             tabs = get_or_create_project_tabs(project, save=False)
@@ -371,7 +371,7 @@ def contactus_update(request, project_short_name):
         else:
             # re-display form view
             if not form.is_valid():
-                print 'Form is invalid  %s' % form.errors
+                print('Form is invalid  %s' % form.errors)
             return render_contactus_form(request, project, form)
 
 
@@ -419,7 +419,7 @@ def notifyAuthorOfProjectApproval(project, request):
 
 def initProject(project):
     
-    print "Initializing project: %s" % project.short_name
+    print("Initializing project: %s" % project.short_name)
                         
     # create project home page
     create_project_home(project, project.author)
@@ -540,7 +540,7 @@ def tags_update(request, project_short_name):
             return HttpResponseRedirect(reverse('project_home', args=[project.short_name.lower()]))
             
         else:
-            print 'Form is invalid  %s' % form.errors
+            print('Form is invalid  %s' % form.errors)
             return render_tags_form(request, project, form)
 
 
@@ -577,13 +577,13 @@ def project_browser(request, project_short_name, tab):
     elif tab == 'all':
         html += render_project_list(project, tab, tag, request.user, None, 'all_projects', None)
     elif tab == 'my':
-        if not request.user.is_anonymous():
+        if not request.user.is_anonymous:
             html += render_project_list(project, tab, tag, request.user, None, 'my_projects', None)
         else:
             html += '<div id="tags_projects" style="display:block; padding:3px"><em class="message">' \
                     'Please login to display your projects.</em></div>'
     elif tab == 'tags':
-        if not request.user.is_anonymous():
+        if not request.user.is_anonymous:
             display = DisplayStatus(True)  # open all sub-widgets by default
             # loop over user tags (sorted by name)
             utags = request.user.profile.tags.all()
@@ -613,22 +613,22 @@ def save_user_tag(request):
         queryDict = getQueryDict(request)
         tagName = queryDict['tag']
         redirect = queryDict['redirect']
-        print 'Saving user tag: %s' % tagName
-        print 'Eventually redirecting to: %s' % redirect
+        print('Saving user tag: %s' % tagName)
+        print('Eventually redirecting to: %s' % redirect)
         
         if isUserLocal(request.user):
             try:
                 tag = ProjectTag.objects.get(name__iexact=tagName)
             except ObjectDoesNotExist:
                 tag = ProjectTag.objects.create(name=tagName)
-                print 'Created new tag: %s' % tag
+                print('Created new tag: %s' % tag)
 
             # add this tag to the user preferences
             utags = request.user.profile.tags
             if tag not in utags.all():
                 utags.add(tag)
                 request.user.profile.save()
-                print 'Tag: %s added to user: %s' % (tagName, request.user)
+                print('Tag: %s added to user: %s' % (tagName, request.user))
 
             # set session flag to preselect a tab
             request.session['PROJECT_BROWSER_TAB'] = 3                
@@ -638,7 +638,7 @@ def save_user_tag(request):
         else:
             url = "http://%s%s?tag=%s&redirect=%s" % (request.user.profile.site.domain, reverse('save_user_tag'),
                                                       tagName, redirect)
-            print 'Redirecting save request to URL=%s' % url
+            print('Redirecting save request to URL=%s' % url)
             # set session flag to eventually force reloading of user tags
             request.session['LAST_ACCESSED'] = 0
             # also set session flag to preselect a tab
@@ -656,8 +656,8 @@ def delete_user_tag(request):
         queryDict = getQueryDict(request)
         tagName = queryDict['tag']
         redirect = queryDict['redirect']
-        print 'Deleting user tag: %s' % tagName
-        print 'Eventually redirecting to: %s' % redirect
+        print('Deleting user tag: %s' % tagName)
+        print('Eventually redirecting to: %s' % redirect)
         
         if isUserLocal(request.user):
             try:
@@ -668,7 +668,7 @@ def delete_user_tag(request):
                     request.user.profile.save()
                     
             except ObjectDoesNotExist:
-                print "Invalid project tag."
+                print("Invalid project tag.")
                 
             # set session flag to preselect a tab
             request.session['PROJECT_BROWSER_TAB'] = 3
@@ -678,7 +678,7 @@ def delete_user_tag(request):
         else:
             url = "http://%s%s?tag=%s&redirect=%s" % (request.user.profile.site.domain, reverse('delete_user_tag'),
                                                       tagName, redirect)
-            print 'Redirecting delete request to URL=%s' % url    
+            print('Redirecting delete request to URL=%s' % url)    
             # set session flag to eventually force reloading of user tags
             request.session['LAST_ACCESSED'] = 0
             # also set session flag to preselect a tab
@@ -704,7 +704,7 @@ def render_project_list(project, tab, tag_name, user, widget_name, widget_id, di
     if tag_name is not None:
         try:
             tag = ProjectTag.objects.get(name__iexact=tag_name)
-            print "tag in render_project_list = ", tag
+            print("tag in render_project_list = ", tag)
         except ObjectDoesNotExist:
             # store error associated with non-existing tag
             tag_error = "Tag does not exist."
@@ -745,7 +745,7 @@ def render_project_list(project, tab, tag_name, user, widget_name, widget_id, di
             html += '<em class="message">'+tag_error+'</em>'
         else:
             # special case: cannot retrieve list of projects for guest user
-            if (tab == 'my' or tab == 'tags') and not user.is_authenticated():
+            if (tab == 'my' or tab == 'tags') and not user.is_authenticated:
                 html += '<em class="message">Please login to display your projects.</em>'
             else:
                 html += '<em class="message">No projects found.</em>'
@@ -788,7 +788,7 @@ def listBrowsableProjects(project, tab, tag, user, widgetName):
         # retrieve all active projects for this user
         projects = getProjectsForUser(user, False)  # includePending==False
     elif tab == 'tags':
-        if not user.is_authenticated():
+        if not user.is_authenticated:
             projects = Project.objects.none()
         else:
             # widgetName==user tag name
@@ -867,7 +867,7 @@ def development_update(request, project_short_name):
             
         # return to form
         else:
-            print 'Form is invalid %s' % form.errors
+            print('Form is invalid %s' % form.errors)
             return render_development_form(request, project, form)
 
 
@@ -933,7 +933,7 @@ def _project_page_update(request, project_short_name,
             
         # return to form
         else:
-            print 'Form is invalid %s' % form.errors
+            print('Form is invalid %s' % form.errors)
             return render(request,
                           form_template,
                           {'title': form_template_title, 'project': project, 'form': form})
@@ -952,9 +952,9 @@ def _getUnsavedProjectSubFolders(project, request):
     """
     
     folders = []
-    for key, value in TOP_SUB_FOLDERS.items():
+    for key, value in list(TOP_SUB_FOLDERS.items()):
         folder = Folder(name=value, project=project, active=False)
-        if request is not None and ("folder_%s" % value) in getQueryDict(request).keys():
+        if request is not None and ("folder_%s" % value) in list(getQueryDict(request).keys()):
             folder.active = True
         folders.append(folder)
     return folders
diff --git a/cog/views/views_search.py b/cog/views/views_search.py
index 44395b33e..d493b4909 100644
--- a/cog/views/views_search.py
+++ b/cog/views/views_search.py
@@ -1,7 +1,7 @@
 from copy import copy, deepcopy
 import json
-import urllib, urllib2
-from urllib2 import HTTPError
+import urllib.request, urllib.parse, urllib.error
+from urllib.error import HTTPError
 
 from cog.config.search import SearchConfigParser
 from cog.forms.forms_search import *
@@ -17,7 +17,7 @@
 from cog.views.utils import getQueryDict
 from django.contrib.auth.decorators import login_required, user_passes_test
 from django.core.exceptions import ObjectDoesNotExist
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.http import HttpResponse, HttpResponseRedirect, HttpResponseForbidden, HttpResponseBadRequest, HttpResponseNotFound
 from django.http.response import HttpResponseServerError
 from django.shortcuts import get_object_or_404, render
@@ -64,7 +64,7 @@ def search(request, project_short_name):
         
     # check permission
     if project.private:
-        if request.user.is_anonymous():
+        if request.user.is_anonymous:
             return HttpResponseRedirect(reverse('login')+"?next=%s" % request.path)
         else:
             if not userHasUserPermission(request.user, project):
@@ -93,7 +93,7 @@ def _addConfigConstraints(searchInput, searchConfig):
     _searchInput = deepcopy(searchInput)
     
     # add fixed constraints - but do NOT override previous values
-    for key, values in searchConfig.fixedConstraints.items():
+    for key, values in list(searchConfig.fixedConstraints.items()):
         if not _searchInput.hasConstraint(key):
             _searchInput.setConstraint(key, values)            
     return _searchInput
@@ -168,11 +168,11 @@ def search_config(request, searchConfig, extra={}, fromRedirectFlag=False):
             
     # GET/POST switch
     queryDict = getQueryDict(request)
-    print "Search() view: HTTP Request method=%s fromRedirectFlag flag=%s HTTP parameters=%s" % (request.method, fromRedirectFlag, queryDict)
+    print("Search() view: HTTP Request method=%s fromRedirectFlag flag=%s HTTP parameters=%s" % (request.method, fromRedirectFlag, queryDict))
     
     if request.method == 'GET':
         # GET pre-seeded search URL -> invoke POST immediately
-        if len(queryDict.keys()) > 0 and not fromRedirectFlag: 
+        if len(list(queryDict.keys())) > 0 and not fromRedirectFlag: 
             return search_post(request, searchInput, searchConfig, extra)
         else:
             return search_get(request, searchInput, searchConfig, extra, fromRedirectFlag)
@@ -196,7 +196,7 @@ def search_get(request, searchInput, searchConfig, extra={}, fromRedirectFlag=Fa
     # GET request after POST redirection
     if fromRedirectFlag:
         
-        print "Retrieving search data from session"
+        print("Retrieving search data from session")
         data = request.session.get(SEARCH_DATA)
             
     # direct GET request: must query for all facet values with project-specific constraints
@@ -206,7 +206,7 @@ def search_get(request, searchInput, searchConfig, extra={}, fromRedirectFlag=Fa
         request.session[SEARCH_PATH] = []
         
         # add project fixed constraints
-        print 'Search GET: adding fixed project constraints'
+        print('Search GET: adding fixed project constraints')
         _searchInput = _addConfigConstraints(searchInput, searchConfig)
         _searchInput.printme()
         
@@ -230,7 +230,7 @@ def search_get(request, searchInput, searchConfig, extra={}, fromRedirectFlag=Fa
             request.session[SEARCH_DATA] = data
             
         except HTTPError:
-            print "HTTP Request Error"
+            print("HTTP Request Error")
             # data = request.session[SEARCH_DATA]
             data[SEARCH_INPUT] = searchInput
 
@@ -241,7 +241,7 @@ def search_get(request, searchInput, searchConfig, extra={}, fromRedirectFlag=Fa
     offset = data[SEARCH_INPUT].offset
     limit = data[SEARCH_INPUT].limit
     if limit > 0 and data.get(SEARCH_OUTPUT, None):
-        currentPage = offset/limit + 1
+        currentPage = offset//limit + 1
         numResults = len(data[SEARCH_OUTPUT].results)
         totResults = data[SEARCH_OUTPUT].counts
         data[SEARCH_PAGES] = []
@@ -302,7 +302,7 @@ def search_post(request, searchInput, searchConfig, extra={}):
     if valid:
                 
         # add project fixed constraints
-        print 'Search POST: adding fixed project constraints'
+        print('Search POST: adding fixed project constraints')
         _searchInput = _addConfigConstraints(searchInput, searchConfig)
         _searchInput.printme()
     
@@ -324,7 +324,7 @@ def search_post(request, searchInput, searchConfig, extra={}):
             # data[FACET_PROFILE] = sorted( facetProfile.getKeys() )  # sort facets by key
             
         except HTTPError:
-            print "HTTP Request Error"
+            print("HTTP Request Error")
             data = request.session[SEARCH_DATA]
             data[SEARCH_INPUT] = searchInput
 
@@ -332,7 +332,7 @@ def search_post(request, searchInput, searchConfig, extra={}):
                                   "Administrator."
     # invalid user input
     else:
-        print "Invalid Search Input"
+        print("Invalid Search Input")
         # re-use previous data (output, profile and any extra argument) from session
         data = request.session[SEARCH_DATA]
         # override search input from request
@@ -348,10 +348,10 @@ def search_post(request, searchInput, searchConfig, extra={}):
     # for key, values in searchInput.constraints.items():
     # note: request parameters do NOT include the project fixed constraints
     req_constraints = []  # latest constraints from request
-    for key, value in queryDict.items():
+    for key, value in list(queryDict.items()):
         if not key in SEARCH_PATH_EXCLUDE and value != 'on':  # value from 'checkbox_...'
             if value is not None and len(value) > 0:  # disregard empty facet
-                print 'key=%s value=%s' % (key, value)
+                print('key=%s value=%s' % (key, value))
                 constraint = (key, value)     
                 req_constraints.append(constraint)
                 if not constraint in sp:
@@ -392,9 +392,9 @@ def metadata_display(request, project_short_name):
     if type == 'File':
         params.append(('dataset_id', dataset_id))
                 
-    url = "http://"+index_node+"/esg-search/search?"+urllib.urlencode(params)
-    print 'Metadata Solr search URL=%s' % url
-    fh = urllib2.urlopen(url)
+    url = "http://"+index_node+"/esg-search/search?"+urllib.parse.urlencode(params)
+    print('Metadata Solr search URL=%s' % url)
+    fh = urllib.request.urlopen(url)
     response = fh.read().decode("UTF-8")
 
     # parse JSON response (containing only one matching 'doc)
@@ -405,10 +405,10 @@ def metadata_display(request, project_short_name):
     parentMetadata = {}
     if type == 'File':
         params = [('type', 'Dataset'), ('id', dataset_id), ("format", "application/solr+json"), ("distrib", "false")]
-        url = "http://"+index_node+"/esg-search/search?"+urllib.urlencode(params)
+        url = "http://"+index_node+"/esg-search/search?"+urllib.parse.urlencode(params)
         # print 'Solr search URL=%s' % url
-        fh = urllib2.urlopen(url)
-        response = fh.read().decode("UTF-8")
+        fh = urllib.request.urlopen(url)
+        response = fh.read()
         jsondoc = json.loads(response)
         parentMetadata = _processDoc(jsondoc["response"]["docs"][0])
     
@@ -538,7 +538,7 @@ def search_profile_export(request, project_short_name):
         scp.write()
         message = 'search_config_exported'
     except Exception as e:
-        print "ERROR: %s" % e
+        print("ERROR: %s" % e)
         message = e       
 
     return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])+"?message=%s" % message)
@@ -559,7 +559,7 @@ def search_profile_import(request, project_short_name):
         scp.read()
         message = 'search_config_imported'
     except Exception as e:
-        print "ERROR: %s" % e
+        print("ERROR: %s" % e)
         message = 'search_config_not_found'        
 
     return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])+"?message=%s" % message)
@@ -607,7 +607,7 @@ def search_profile_config(request, project_short_name):
             return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()]))
             
         else:
-            print 'Form is invalid: %s' % form
+            print('Form is invalid: %s' % form)
             return render_search_profile_form(request, project, form, search_groups)
             
 
@@ -663,7 +663,7 @@ def search_facet_add(request, project_short_name):
             return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])) 
         
         else:     
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
             
             # must retrieve facets again
             facets = _queryFacets(request, project)
@@ -698,7 +698,7 @@ def search_group_add(request, project_short_name):
             return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])) 
         
         else:     
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
                         
             return render_search_group_form(request, project, form)
 
@@ -727,7 +727,7 @@ def search_group_update(request, group_id):
             return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])) 
         
         else:     
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
             return render_search_group_form(request, project, form)
 
 
@@ -759,7 +759,7 @@ def search_facet_update(request, facet_id):
             return HttpResponseRedirect(reverse('search_profile_config', args=[project.short_name.lower()])) 
         
         else:     
-            print 'Form is invalid: %s' % form.errors
+            print('Form is invalid: %s' % form.errors)
             return render_search_facet_form(request, project, form, facets)
 
 
@@ -850,9 +850,9 @@ def search_files(request, dataset_id, index_node):
     else:
         params.append(("distrib", "false"))
  
-    url = "http://"+index_node+"/esg-search/search?"+urllib.urlencode(params)
-    print 'Searching for files: URL=%s' % url
-    fh = urllib2.urlopen(url)
+    url = "http://"+index_node+"/esg-search/search?"+urllib.parse.urlencode(params)
+    print('Searching for files: URL=%s' % url)
+    fh = urllib.request.urlopen(url)
     response = fh.read().decode("UTF-8")
 
     return HttpResponse(response, content_type="application/json")
@@ -863,7 +863,7 @@ def search_reload(request):
        including constraints and results."""
     
     if request.session.get(LAST_SEARCH_URL, None):
-        print 'Reloading search page: %s' % request.session[LAST_SEARCH_URL]
+        print('Reloading search page: %s' % request.session[LAST_SEARCH_URL])
         request.session[SEARCH_REDIRECT] = True  # flag to retrieve constraints, results
         return HttpResponseRedirect(request.session[LAST_SEARCH_URL])  # just like after the last POST
         
@@ -920,13 +920,13 @@ def search_profile_order(request, project_short_name):
         valid = True  # form data validation flag
         errors = {} # form validation errors
         
-        for group, facets in groups.items():
+        for group, facets in list(groups.items()):
                         
             group_key = SEARCH_GROUP_KEY + str(group.name)
             group_order = request.POST[group_key]
             group.order = int(group_order) # reassign the group orde WITHOUT saving to the database for now
             # validate group order
-            if group_order in groupOrderMap.values():
+            if group_order in list(groupOrderMap.values()):
                 valid = False
                 errors[group_key] = "Duplicate search facet number: %d" % int(group_order)
             else:
@@ -939,7 +939,7 @@ def search_profile_order(request, project_short_name):
                 facet_order = request.POST[facet_key]
                 facet.order = facet_order
                 # validate facet order within this group
-                if facet_order in facetOrderMap.values():
+                if facet_order in list(facetOrderMap.values()):
                     valid = False
                     errors[facet_key] = "Duplicate facet number: %d" % int(facet_order)
                 else:
@@ -949,7 +949,7 @@ def search_profile_order(request, project_short_name):
         if valid:
             
             # save new ordering for groups, facets
-            for group, facets in groups.items():
+            for group, facets in list(groups.items()):
                 group.save()
                 for facet in facets:
                     facet.save()
@@ -991,21 +991,20 @@ def citation_display(request):
     url = request.GET.get('url', '')
 
     try:
-        fh = urllib2.urlopen(url)
+        fh = urllib.request.urlopen(url)
         response = fh.read()
-        headers = fh.info().dict
-    except HTTPError, e:
-        print('HTTPError %s for %s' % (str(e.code), url))
+    except HTTPError as e:
+        print(('HTTPError %s for %s' % (str(e.code), url)))
         return HttpResponseNotFound()
 
-    if int(headers['x-cera-rc']) > 0:
-        print 'Citation not found: %s' % url
+    if int(fh.getheader('x-cera-rc')) > 0:
+        print('Citation not found: %s' % url)
         return HttpResponseNotFound()
 
     try:
         json.loads(response)
-    except ValueError, e:
-        print 'Citation not valid json: %s' % url
+    except ValueError as e:
+        print('Citation not valid json: %s' % url)
         return HttpResponseNotFound()
 
     return HttpResponse(response, content_type="application/json")
diff --git a/cog/views/views_share.py b/cog/views/views_share.py
index 9f1704d16..a4b23b02a 100644
--- a/cog/views/views_share.py
+++ b/cog/views/views_share.py
@@ -97,7 +97,7 @@ def share_projects(request):
         
         # list projects from this node
         projects = {}
-        print 'Listing ACTIVE projects for current site=%s' % current_site
+        print('Listing ACTIVE projects for current site=%s' % current_site)
         for project in Project.objects.filter(active=True).filter(site=current_site):
             projects[project.short_name] = serialize_project(project)
             
@@ -123,7 +123,7 @@ def share_groups(request):
         response_data['site'] = serialize_site(current_site)
         
         # list groups from this node, index by group name
-        print 'Listing visible groups for current site=%s' % current_site
+        print('Listing visible groups for current site=%s' % current_site)
         groups = {}
         for group in registrationService.listGroups():
             if group['visible'] and group['name'].lower() != 'wheel':
@@ -149,7 +149,7 @@ def share_user(request):
              
         except ObjectDoesNotExist:
             # return empty dictionary
-            print 'User with openid=%s found at this site' % openid
+            print('User with openid=%s found at this site' % openid)
             users = {}
         
         response_data["users"] = users
@@ -169,7 +169,7 @@ def sync_projects(request):
     
     return render(request,
                   'cog/admin/sync_projects.html', 
-                  {'sites':sorted(sites.iteritems(), key=lambda (siteid, sitedict): sitedict['name']), 
+                  {'sites':sorted(iter(sites.items()), key=lambda siteid_sitedict: siteid_sitedict[1]['name']), 
                    'totalNumberOfProjects':totalNumberOfProjects, 'totalNumberOfUsers':totalNumberOfUsers })
         
     
\ No newline at end of file
diff --git a/cog/views/views_status.py b/cog/views/views_status.py
index a961935cc..ddc4560c7 100644
--- a/cog/views/views_status.py
+++ b/cog/views/views_status.py
@@ -1,7 +1,7 @@
 from django.shortcuts import get_object_or_404, render, redirect
 from django.template import RequestContext
 from django.http import HttpResponseRedirect, HttpResponseForbidden, HttpResponseServerError
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.contrib.auth.decorators import login_required, user_passes_test, permission_required
 from django.forms.models import modelformset_factory, inlineformset_factory
 import string
diff --git a/filebrowser/actions.py b/filebrowser/actions.py
index fd275c066..2df6db6ff 100644
--- a/filebrowser/actions.py
+++ b/filebrowser/actions.py
@@ -53,30 +53,30 @@ def transpose_image(request, fileobjects, operation):
 
 def flip_horizontal(request, fileobjects):
     transpose_image(request, fileobjects, 0)
-flip_horizontal.short_description = _(u'Flip horizontal')
+flip_horizontal.short_description = _('Flip horizontal')
 flip_horizontal.applies_to = applies_to_all_images
 
 
 def flip_vertical(request, fileobjects):
     transpose_image(request, fileobjects, 1)
-flip_vertical.short_description = _(u'Flip vertical')
+flip_vertical.short_description = _('Flip vertical')
 flip_vertical.applies_to = applies_to_all_images
 
 
 def rotate_90_clockwise(request, fileobjects):
     transpose_image(request, fileobjects, 4)
-rotate_90_clockwise.short_description = _(u'Rotate 90° CW')
+rotate_90_clockwise.short_description = _('Rotate 90° CW')
 rotate_90_clockwise.applies_to = applies_to_all_images
 
 
 def rotate_90_counterclockwise(request, fileobjects):
     transpose_image(request, fileobjects, 2)
-rotate_90_counterclockwise.short_description = _(u'Rotate 90° CCW')
+rotate_90_counterclockwise.short_description = _('Rotate 90° CCW')
 rotate_90_counterclockwise.applies_to = applies_to_all_images
 
 
 def rotate_180(request, fileobjects):
     transpose_image(request, fileobjects, 3)
-rotate_180.short_description = _(u'Rotate 180°')
+rotate_180.short_description = _('Rotate 180°')
 rotate_180.applies_to = applies_to_all_images
 
diff --git a/filebrowser/base.py b/filebrowser/base.py
index ad05b21c8..c47a5a260 100644
--- a/filebrowser/base.py
+++ b/filebrowser/base.py
@@ -4,7 +4,7 @@
 import mimetypes
 import os, shutil, re, datetime, time
 
-from django.utils.encoding import smart_str, smart_unicode
+from django.utils.encoding import smart_bytes, smart_text
 from django.utils.translation import ugettext as _
 from filebrowser.functions import (get_file_type, url_join, get_version_path, get_original_path, sort_by_attr, 
                                    version_generator, path_strip, url_strip, validate_path)
@@ -132,7 +132,7 @@ def files_walk_total(self):
     def files_listing_filtered(self):
         "Returns FileObjects for filtered files in listing"
         if self.filter_func:
-            listing = filter(self.filter_func, self.files_listing_total())
+            listing = list(filter(self.filter_func, self.files_listing_total()))
         else:
             listing = self.files_listing_total()
         self._results_listing_filtered = len(listing)
@@ -141,7 +141,7 @@ def files_listing_filtered(self):
     def files_walk_filtered(self):
         "Returns FileObjects for filtered files in walk"
         if self.filter_func:
-            listing = filter(self.filter_func, self.files_walk_total())
+            listing = list(filter(self.filter_func, self.files_walk_total()))
         else:
             listing = self.files_walk_total()
         self._results_walk_filtered = len(listing)
@@ -199,10 +199,10 @@ def __init__(self, path, site=None):
 
     
     def __str__(self):
-        return smart_str(self.path)
+        return smart_bytes(self.path)
     
     def __unicode__(self):
-        return smart_unicode(self.path)
+        return smart_text(self.path)
     
     @property
     def name(self):
diff --git a/filebrowser/decorators.py b/filebrowser/decorators.py
index bd309f77f..0c4cadb1f 100644
--- a/filebrowser/decorators.py
+++ b/filebrowser/decorators.py
@@ -3,7 +3,7 @@
 # DJANGO IMPORTS
 from django.http import HttpResponseRedirect
 from django.utils.translation import ugettext as _
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.contrib import messages
 from django.core.exceptions import ImproperlyConfigured
 
@@ -20,7 +20,7 @@ def path_exists(site, function):
     def decorator(request, *args, **kwargs):
         if get_path('', site=site) == None:
             # The DIRECTORY does not exist, raise an error to prevent eternal redirecting.
-            raise ImproperlyConfigured, _("Error finding Upload-Folder (MEDIA_ROOT + DIRECTORY). Maybe it does not exist?")
+            raise ImproperlyConfigured(_("Error finding Upload-Folder (MEDIA_ROOT + DIRECTORY). Maybe it does not exist?"))
         if get_path(request.GET.get('dir', ''), site=site) == None:
             msg = _('The requested Folder does not exist.')
             messages.add_message(request, messages.ERROR, msg)
diff --git a/filebrowser/fields.py b/filebrowser/fields.py
index 7f922dbdc..dc6fd304a 100644
--- a/filebrowser/fields.py
+++ b/filebrowser/fields.py
@@ -8,7 +8,6 @@
 from django import forms
 from django.forms.widgets import Input
 from django.db.models.fields import Field, CharField
-from django.utils.encoding import force_unicode
 from django.template.loader import render_to_string
 from django.utils.translation import ugettext_lazy as _
 from django.core import urlresolvers
@@ -62,7 +61,7 @@ def render(self, name, value, attrs=None):
 class FileBrowseFormField(forms.CharField):
     
     default_error_messages = {
-        'extension': _(u'Extension %(ext)s is not allowed. Only %(allowed)s is allowed.'),
+        'extension': _('Extension %(ext)s is not allowed. Only %(allowed)s is allowed.'),
     }
     
     def __init__(self, max_length=None, min_length=None, site=None, directory=None, extensions=None, format=None, *args, **kwargs):
@@ -85,9 +84,8 @@ def clean(self, value):
         return value
 
 
-class FileBrowseField(CharField):
+class FileBrowseField(CharField, metaclass=models.SubfieldBase):
     description = "FileBrowseField"
-    __metaclass__ = models.SubfieldBase
     
     def __init__(self, *args, **kwargs):
         self.site = kwargs.pop('filebrowser_site', site)
diff --git a/filebrowser/forms.py b/filebrowser/forms.py
index 4cd9973b1..8eae475e9 100644
--- a/filebrowser/forms.py
+++ b/filebrowser/forms.py
@@ -17,12 +17,12 @@
 
 # CHOICES
 TRANSPOSE_CHOICES = (
-    ("", u"-----"),
-    ("0", _(u"Flip horizontal")),
-    ("1", _(u"Flip vertical")),
-    ("2", _(u"Rotate 90° CW")),
-    ("4", _(u"Rotate 90° CCW")),
-    ("3", _(u"Rotate 180°")),
+    ("", "-----"),
+    ("0", _("Flip horizontal")),
+    ("1", _("Flip vertical")),
+    ("2", _("Rotate 90° CW")),
+    ("4", _("Rotate 90° CCW")),
+    ("3", _("Rotate 180°")),
 )
 
 
@@ -36,16 +36,16 @@ def __init__(self, path, *args, **kwargs):
         self.site = kwargs.pop("filebrowser_site", None)
         super(CreateDirForm, self).__init__(*args, **kwargs)
         
-    name = forms.CharField(widget=forms.TextInput(attrs=dict({ 'class': 'vTextField' }, max_length=50, min_length=3)), label=_(u'Name'), help_text=_(u'Only letters, numbers, underscores, spaces and hyphens are allowed.'), required=True)
+    name = forms.CharField(widget=forms.TextInput(attrs=dict({ 'class': 'vTextField' }, max_length=50, min_length=3)), label=_('Name'), help_text=_('Only letters, numbers, underscores, spaces and hyphens are allowed.'), required=True)
     
     def clean_name(self):
         if self.cleaned_data['name']:
             # only letters, numbers, underscores, spaces and hyphens are allowed.
             if not alnum_name_re.search(self.cleaned_data['name']):
-                raise forms.ValidationError(_(u'Only letters, numbers, underscores, spaces and hyphens are allowed.'))
+                raise forms.ValidationError(_('Only letters, numbers, underscores, spaces and hyphens are allowed.'))
             # Folder must not already exist.
             if self.site.storage.isdir(os.path.join(self.path, convert_filename(self.cleaned_data['name']))):
-                raise forms.ValidationError(_(u'The Folder already exists.'))
+                raise forms.ValidationError(_('The Folder already exists.'))
         return convert_filename(self.cleaned_data['name'])
 
 
@@ -54,8 +54,8 @@ class ChangeForm(forms.Form):
     Form for renaming a file/folder.
     """
     
-    custom_action = forms.ChoiceField(label=_(u'Actions'), required=False)
-    name = forms.CharField(widget=forms.TextInput(attrs=dict({ 'class': 'vTextField' }, max_length=50, min_length=3)), label=_(u'Name'), help_text=_(u'Only letters, numbers, underscores, spaces and hyphens are allowed.'), required=True)
+    custom_action = forms.ChoiceField(label=_('Actions'), required=False)
+    name = forms.CharField(widget=forms.TextInput(attrs=dict({ 'class': 'vTextField' }, max_length=50, min_length=3)), label=_('Name'), help_text=_('Only letters, numbers, underscores, spaces and hyphens are allowed.'), required=True)
     
     def __init__(self, *args, **kwargs):
         self.path = kwargs.pop("path", None)
@@ -65,7 +65,7 @@ def __init__(self, *args, **kwargs):
         super(ChangeForm, self).__init__(*args, **kwargs)
         
         # Initialize choices of custom actions 
-        choices = [("",u"-----"),]
+        choices = [("","-----"),]
         
         for name, action in self.site.applicable_actions(self.fileobject):
             choices.append((name, action.short_description))
@@ -76,12 +76,12 @@ def clean_name(self):
         if self.cleaned_data['name']:
             # only letters, numbers, underscores, spaces and hyphens are allowed.
             if not alnum_name_re.search(self.cleaned_data['name']):
-                raise forms.ValidationError(_(u'Only letters, numbers, underscores, spaces and hyphens are allowed.'))
+                raise forms.ValidationError(_('Only letters, numbers, underscores, spaces and hyphens are allowed.'))
             #  folder/file must not already exist.
             if self.site.storage.isdir(os.path.join(self.path, convert_filename(self.cleaned_data['name']))) and os.path.join(self.path, convert_filename(self.cleaned_data['name'])) != self.fileobject.path:
-                raise forms.ValidationError(_(u'The Folder already exists.'))
+                raise forms.ValidationError(_('The Folder already exists.'))
             elif self.site.storage.isfile(os.path.join(self.path, convert_filename(self.cleaned_data['name'])))  and os.path.join(self.path, convert_filename(self.cleaned_data['name'])) != self.fileobject.path:
-                raise forms.ValidationError(_(u'The File already exists.'))
+                raise forms.ValidationError(_('The File already exists.'))
         return convert_filename(self.cleaned_data['name'])
 
 
diff --git a/filebrowser/functions.py b/filebrowser/functions.py
index 8c86f9ca2..399e040b5 100644
--- a/filebrowser/functions.py
+++ b/filebrowser/functions.py
@@ -8,7 +8,7 @@
 # django imports
 from django.utils.translation import ugettext as _
 from django.core.files import File
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import smart_text
 
 # filebrowser imports
 from filebrowser.settings import *
@@ -125,9 +125,9 @@ def sort_by_attr(seq, attr):
     # (seq[i].attr, i, seq[i]) and sort it. The second item of tuple is needed not
     # only to provide stable sorting, but mainly to eliminate comparison of objects
     # (which can be expensive or prohibited) in case of equal attribute values.
-    intermed = map(None, map(getattr, seq, (attr,)*len(seq)), xrange(len(seq)), seq)
+    intermed = map(None, list(map(getattr, seq, (attr,)*len(seq))), range(len(seq)), seq)
     intermed.sort()
-    return map(operator.getitem, intermed, (-1,) * len(intermed))
+    return list(map(operator.getitem, intermed, (-1,) * len(intermed)))
 
 
 def url_join(*args):
@@ -166,7 +166,7 @@ def get_file(path, filename, site=None):
     """
     Get file (or folder).
     """
-    converted_path = smart_unicode(os.path.join(site.directory, path, filename))
+    converted_path = smart_text(os.path.join(site.directory, path, filename))
     if not site.storage.isfile(converted_path) and not site.storage.isdir(converted_path):
         return None
     return filename
@@ -179,7 +179,7 @@ def get_file_type(filename):
     
     file_extension = os.path.splitext(filename)[1].lower()
     file_type = ''
-    for k,v in EXTENSIONS.iteritems():
+    for k,v in EXTENSIONS.items():
         for extension in v:
             if file_extension == extension.lower():
                 file_type = k
@@ -261,7 +261,7 @@ def handle_file_upload(path, file, site):
     try:
         file_path = os.path.join(path, file.name)
         uploadedfile = site.storage.save(file_path, file)
-    except Exception, inst:
+    except Exception as inst:
         raise inst
     return uploadedfile
 
@@ -273,7 +273,7 @@ def is_selectable(filename, selecttype):
     
     file_extension = os.path.splitext(filename)[1].lower()
     select_types = []
-    for k,v in SELECT_FORMATS.iteritems():
+    for k,v in SELECT_FORMATS.items():
         for extension in v:
             if file_extension == extension.lower():
                 select_types.append(k)
@@ -309,7 +309,7 @@ def version_generator(value, version_prefix, force=None, site=None):
         version = scale_and_crop(im, VERSIONS[version_prefix]['width'], VERSIONS[version_prefix]['height'], VERSIONS[version_prefix]['opts'])
         if not version:
             version = im
-        if 'methods' in VERSIONS[version_prefix].keys():
+        if 'methods' in list(VERSIONS[version_prefix].keys()):
             for m in VERSIONS[version_prefix]['methods']:
                 if callable(m):
                     version = m(version)
@@ -379,7 +379,7 @@ def convert_filename(value):
         chunks = value.split(os.extsep)
         normalized = []
         for v in chunks:
-            v = unicodedata.normalize('NFKD', unicode(v)).encode('ascii', 'ignore')
+            v = unicodedata.normalize('NFKD', str(v)).encode('ascii', 'ignore')
             v = re.sub('[^\w\s-]', '', v).strip()
             normalized.append(v)
 
diff --git a/filebrowser/management/commands/fb_version_generate.py b/filebrowser/management/commands/fb_version_generate.py
index 595965e42..4728a9e10 100644
--- a/filebrowser/management/commands/fb_version_generate.py
+++ b/filebrowser/management/commands/fb_version_generate.py
@@ -33,7 +33,7 @@ def handle(self, *args, **options):
             for version in VERSIONS:
                 self.stdout.write(' * %s\n' % version)
             
-            version_name = raw_input('(leave blank to generate all versions): ')
+            version_name = input('(leave blank to generate all versions): ')
             
             if version_name == "":
                 selected_version = None
@@ -52,7 +52,7 @@ def handle(self, *args, **options):
         filter_re = []
         for exp in EXCLUDE:
            filter_re.append(re.compile(exp))
-        for k,v in VERSIONS.iteritems():
+        for k,v in VERSIONS.items():
             exp = (r'_%s(%s)') % (k, '|'.join(EXTENSION_LIST))
             filter_re.append(re.compile(exp))
         
diff --git a/filebrowser/management/commands/fb_version_remove.py b/filebrowser/management/commands/fb_version_remove.py
index cb698a419..78f91d36e 100644
--- a/filebrowser/management/commands/fb_version_remove.py
+++ b/filebrowser/management/commands/fb_version_remove.py
@@ -34,7 +34,7 @@ def handle(self, *args, **options):
         while 1:
             self.stdout.write('\nOlder versions of the FileBrowser used to prefix the filename with the version name.\n')
             self.stdout.write('Current version of the FileBrowser adds the version name as suffix.\n')
-            prefix_or_suffix = raw_input('"p" for prefix or "s" for suffix (leave blank for "%s"): ' % default_prefix_or_suffix)
+            prefix_or_suffix = input('"p" for prefix or "s" for suffix (leave blank for "%s"): ' % default_prefix_or_suffix)
             
             if default_prefix_or_suffix and prefix_or_suffix == '':
                 prefix_or_suffix = default_prefix_or_suffix
@@ -46,7 +46,7 @@ def handle(self, *args, **options):
         
         # get version name
         while 1:
-            version_name = raw_input('\nversion name as defined with VERSIONS: ')
+            version_name = input('\nversion name as defined with VERSIONS: ')
             
             if version_name == "":
                 self.stderr.write('Error: You have to enter a version name.\n')
@@ -82,7 +82,7 @@ def handle(self, *args, **options):
         # ask to make sure
         do_remove = ""
         self.stdout.write('Are Sure you want to delete these files?\n')
-        do_remove = raw_input('"y" for Yes or "n" for No (leave blank for "n"): ')
+        do_remove = input('"y" for Yes or "n" for No (leave blank for "n"): ')
         
         # if "yes" we delete. any different case we finish without removing anything
         if do_remove == "y":
diff --git a/filebrowser/settings.py b/filebrowser/settings.py
index 3069e89f5..7797b6a1c 100644
--- a/filebrowser/settings.py
+++ b/filebrowser/settings.py
@@ -97,7 +97,7 @@
 # Exclude files matching any of the following regular expressions
 # Default is to exclude 'thumbnail' style naming of image-thumbnails.
 EXTENSION_LIST = []
-for exts in EXTENSIONS.values():
+for exts in list(EXTENSIONS.values()):
     EXTENSION_LIST += exts
 EXCLUDE = getattr(settings, 'FILEBROWSER_EXCLUDE', (r'_(%(exts)s)_.*_q\d{1,3}\.(%(exts)s)'
                                                     % {'exts': ('|'.join(EXTENSION_LIST))},))
@@ -122,7 +122,7 @@
 # Traverse directories when searching
 SEARCH_TRAVERSE = getattr(settings, "FILEBROWSER_SEARCH_TRAVERSE", False)
 # Default Upload and Version Permissions
-DEFAULT_PERMISSIONS = getattr(settings, "FILEBROWSER_DEFAULT_PERMISSIONS", 0755)
+DEFAULT_PERMISSIONS = getattr(settings, "FILEBROWSER_DEFAULT_PERMISSIONS", 0o755)
 
 # EXTRA TRANSLATION STRINGS
 # The following strings are not availabe within views or templates
diff --git a/filebrowser/sites.py b/filebrowser/sites.py
index e0a496c53..8403f498b 100644
--- a/filebrowser/sites.py
+++ b/filebrowser/sites.py
@@ -25,10 +25,10 @@
 from django.views.decorators.cache import never_cache
 from django.utils.translation import ugettext as _
 from django import forms
-from django.core.urlresolvers import reverse, get_urlconf, get_resolver
+from django.urls import reverse, get_urlconf, get_resolver
 from django.dispatch import Signal
 from django.core.paginator import Paginator, InvalidPage, EmptyPage
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import smart_text
 from django.contrib import messages
 from django.views.decorators.csrf import csrf_exempt, csrf_protect
 from django.core.files.base import ContentFile
@@ -70,19 +70,19 @@ def get_site_dict(app_name='filebrowser'):
     Return a dict with all *deployed* FileBrowser sites that have 
     a given app_name.
     """
-    if not _sites_cache.has_key(app_name):
+    if app_name not in _sites_cache:
         return {}
     # Get names of all deployed filebrowser sites with a give app_name
     deployed = get_resolver(get_urlconf()).app_dict[app_name]
     # Get the deployed subset from the cache
-    return dict((k,v) for k, v in _sites_cache[app_name].iteritems() if k in deployed)
+    return dict((k,v) for k, v in _sites_cache[app_name].items() if k in deployed)
 
 
 def register_site(app_name, site_name, site):
     """
     Add a site into the site dict.
     """
-    if not _sites_cache.has_key(app_name):
+    if app_name not in _sites_cache:
         _sites_cache[app_name] = {}
     _sites_cache[app_name][site_name] = site
 
@@ -96,7 +96,7 @@ def get_default_site(app_name='filebrowser'):
     resolver = get_resolver(get_urlconf())
     name = 'filebrowser'
 
-    # Django's default name resolution method (see django.core.urlresolvers.reverse())
+    # Django's default name resolution method (see django.urls.reverse())
     app_list = resolver.app_dict[app_name]
     if not name in app_list:
         name = app_list[0]
@@ -196,7 +196,7 @@ def actions(self):
         Get all the enabled actions as a list of (name, func). The list
         is sorted alphabetically by actions names
         """
-        res = self._actions.items()
+        res = list(self._actions.items())
         res.sort(key=lambda name_func: name_func[0])
         return res
 
@@ -212,7 +212,7 @@ def browse(self, request):
         filter_re = []
         for exp in EXCLUDE:
            filter_re.append(re.compile(exp))
-        for k,v in VERSIONS.iteritems():
+        for k,v in VERSIONS.items():
             exp = (r'_%s(%s)') % (k, '|'.join(EXTENSION_LIST))
             filter_re.append(re.compile(exp))
             
@@ -233,7 +233,7 @@ def filter_browse(item):
             return True
         
         query = request.GET.copy()
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         
         filelisting = FileListing(path,
             filter_func=filter_browse,
@@ -283,7 +283,7 @@ def filter_browse(item):
                        'page': page,
                        'filelisting': filelisting,
                        'query': query,
-                       'title': _(u'FileBrowser'),
+                       'title': _('FileBrowser'),
                        'settings_var': get_settings_var(directory=self.directory),
                        'breadcrumbs': get_breadcrumbs(query, query.get('dir', '')),
                        'breadcrumbs_title': "",
@@ -301,7 +301,7 @@ def createdir(self, request):
         """
         from filebrowser.forms import CreateDirForm
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         
         if request.method == 'POST':
             form = CreateDirForm(path, request.POST, filebrowser_site=self)
@@ -316,7 +316,8 @@ def createdir(self, request):
                     messages.add_message(request, messages.SUCCESS, _('The Folder %s was successfully created.') % form.cleaned_data['name'])
                     redirect_url = reverse("filebrowser:fb_browse", current_app=self.name) + query_helper(query, "ot=desc,o=date", "ot,o,filter_type,filter_date,q,p")
                     return HttpResponseRedirect(redirect_url)
-                except OSError, (errno, strerror):
+                except OSError as xxx_todo_changeme:
+                    (errno, strerror) = xxx_todo_changeme.args
                     if errno == 13:
                         form.errors['name'] = forms.util.ErrorList([_('Permission denied.')])
                     else:
@@ -328,10 +329,10 @@ def createdir(self, request):
                       'filebrowser/createdir.html', 
                       {'form': form,
                        'query': query,
-                       'title': _(u'New Folder'),
+                       'title': _('New Folder'),
                        'settings_var': get_settings_var(directory=self.directory),
                        'breadcrumbs': get_breadcrumbs(query, query.get('dir', '')),
-                       'breadcrumbs_title': _(u'New Folder'),
+                       'breadcrumbs_title': _('New Folder'),
                        'filebrowser_site': self } ) #context_instance=Context(request, current_app=self.name))
     
 
@@ -341,15 +342,15 @@ def upload(self, request):
         Multipe File Upload.
         """
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         
         return render(request,
                       'filebrowser/upload.html', 
                       { 'query': query,
-                       'title': _(u'Select files to upload'),
+                       'title': _('Select files to upload'),
                        'settings_var': get_settings_var(directory=self.directory),
                        'breadcrumbs': get_breadcrumbs(query, query.get('dir', '')),
-                       'breadcrumbs_title': _(u'Upload'),
+                       'breadcrumbs_title': _('Upload'),
                        'filebrowser_site': self }) #context_instance=Context(request, current_app=self.name))
 
     @filebrowser_check()
@@ -358,7 +359,7 @@ def delete_confirm(self, request):
         Delete existing File/Directory.
         """
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         fileobject = FileObject(os.path.join(path, query.get('filename', '')), site=self)
         if fileobject.filetype == "Folder":
             filelisting = FileListing(os.path.join(path, fileobject.filename),
@@ -380,10 +381,10 @@ def delete_confirm(self, request):
             'filelisting': filelisting,
             'additional_files': additional_files,
             'query': query,
-            'title': _(u'Confirm delete'),
+            'title': _('Confirm delete'),
             'settings_var': get_settings_var(directory=self.directory),
             'breadcrumbs': get_breadcrumbs(query, query.get('dir', '')),
-            'breadcrumbs_title': _(u'Confirm delete'),
+            'breadcrumbs_title': _('Confirm delete'),
             'filebrowser_site': self
         }) #, context_instance=Context(request, current_app=self.name))
 
@@ -397,7 +398,7 @@ def delete(self, request):
         Delete existing File/Directory.
         """
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         fileobject = FileObject(os.path.join(path, query.get('filename', '')), site=self)
         
         if request.GET:
@@ -406,7 +407,7 @@ def delete(self, request):
                 # COG: must delete Doc objects
                 docs = Doc.objects.filter(file=fileobject.path)
                 for doc in docs:
-                    print 'Deleting doc=%s' % doc
+                    print('Deleting doc=%s' % doc)
                     doc.delete()
                 
                 self.filebrowser_pre_delete.send(sender=request, path=fileobject.path, name=fileobject.filename)
@@ -414,7 +415,9 @@ def delete(self, request):
                 fileobject.delete()
                 self.filebrowser_post_delete.send(sender=request, path=fileobject.path, name=fileobject.filename)
                 messages.add_message(request, messages.SUCCESS, _('Successfully deleted %s') % fileobject.filename)
-            except OSError, (errno, strerror):
+            except OSError as xxx_todo_changeme2:
+                # TODO: define error-message
+                (errno, strerror) = xxx_todo_changeme2.args
                 # TODO: define error-message
                 pass
         redirect_url = reverse("filebrowser:fb_browse", current_app=self.name) + query_helper(query, "", "filename,filetype")
@@ -436,7 +439,7 @@ def detail(self, request):
         """
         from filebrowser.forms import ChangeForm
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         fileobject = FileObject(os.path.join(path, query.get('filename', '')), site=self)
         
         if request.method == 'POST':
@@ -467,7 +470,8 @@ def detail(self, request):
                     else:
                         redirect_url = reverse("filebrowser:fb_browse", current_app=self.name) + query_helper(query, "", "filename")
                     return HttpResponseRedirect(redirect_url)
-                except OSError, (errno, strerror):
+                except OSError as xxx_todo_changeme1:
+                    (errno, strerror) = xxx_todo_changeme1.args
                     form.errors['name'] = forms.util.ErrorList([_('Error.')])
         else:
             form = ChangeForm(initial={"name": fileobject.filename}, path=path, fileobject=fileobject, filebrowser_site=self)
@@ -476,10 +480,10 @@ def detail(self, request):
             'form': form,
             'fileobject': fileobject,
             'query': query,
-            'title': u'%s' % fileobject.filename,
+            'title': '%s' % fileobject.filename,
             'settings_var': get_settings_var(directory=self.directory),
             'breadcrumbs': get_breadcrumbs(query, query.get('dir', '')),
-            'breadcrumbs_title': u'%s' % fileobject.filename,
+            'breadcrumbs_title': '%s' % fileobject.filename,
             'filebrowser_site': self
         }) # context_instance=Context(request, current_app=self.name))
 
@@ -488,7 +492,7 @@ def version(self, request):
         Version detail.
         """
         query = request.GET
-        path = u'%s' % os.path.join(self.directory, query.get('dir', ''))
+        path = '%s' % os.path.join(self.directory, query.get('dir', ''))
         fileobject = FileObject(os.path.join(path, query.get('filename', '')), site=self)
         
         return render(request, 'filebrowser/version.html', {
@@ -518,7 +522,7 @@ def _upload_file(self, request):
                 # TODO: This needs some attention, do we use this at all?
                 folder = request.POST.get('folder')
                 if len(request.FILES) == 1:
-                    filedata = request.FILES.values()[0]
+                    filedata = list(request.FILES.values())[0]
                 else:
                     raise Http404('Invalid request! Multiple files included.')
                 # filedata.name = convert_filename(upload.name)
@@ -540,11 +544,11 @@ def _upload_file(self, request):
             uploadedfile = handle_file_upload(path, filedata, site=self)
             
             if file_already_exists:
-                old_file = smart_unicode(file_name)
-                new_file = smart_unicode(uploadedfile)
+                old_file = smart_text(file_name)
+                new_file = smart_text(uploadedfile)
                 self.storage.move(new_file, old_file, allow_overwrite=True)
             
-            self.filebrowser_post_upload.send(sender=request, path=request.POST.get('folder'), file=FileObject(smart_unicode(file_name), site=self))
+            self.filebrowser_post_upload.send(sender=request, path=request.POST.get('folder'), file=FileObject(smart_text(file_name), site=self))
             
             # let Ajax Upload know whether we saved it or not
             ret_json = {'success': True, 'filename': filedata.name}
@@ -557,7 +561,7 @@ def _upload_file(self, request):
 site = FileBrowserSite(name='filebrowser', storage=storage)
 
 # Default actions
-from actions import *
+from .actions import *
 site.add_action(flip_horizontal)
 site.add_action(flip_vertical)
 site.add_action(rotate_90_clockwise)
diff --git a/filebrowser/sites.py-original b/filebrowser/sites.py-original
index a45f67491..4b5134ada 100644
--- a/filebrowser/sites.py-original
+++ b/filebrowser/sites.py-original
@@ -12,7 +12,7 @@ from django.contrib.admin.views.decorators import staff_member_required
 from django.views.decorators.cache import never_cache
 from django.utils.translation import ugettext as _
 from django import forms
-from django.core.urlresolvers import reverse, get_urlconf, get_resolver
+from django.urls import reverse, get_urlconf, get_resolver
 from django.dispatch import Signal
 from django.core.paginator import Paginator, InvalidPage, EmptyPage
 from django.utils.encoding import smart_unicode
@@ -84,7 +84,7 @@ def get_default_site(app_name='filebrowser'):
     resolver = get_resolver(get_urlconf())
     name = 'filebrowser'
 
-    # Django's default name resolution method (see django.core.urlresolvers.reverse())
+    # Django's default name resolution method (see django.urls.reverse())
     app_list = resolver.app_dict[app_name]
     if not name in app_list:
         name = app_list[0]
diff --git a/filebrowser/templatetags/fb_csrf.py b/filebrowser/templatetags/fb_csrf.py
index 93803fae4..48bdeef89 100644
--- a/filebrowser/templatetags/fb_csrf.py
+++ b/filebrowser/templatetags/fb_csrf.py
@@ -12,9 +12,9 @@ def render(self, context):
         csrf_token = context.get('csrf_token', None)
         if csrf_token:
             if csrf_token == 'NOTPROVIDED':
-                return mark_safe(u"")
+                return mark_safe("")
             else:
-                return mark_safe(u"<div style='display:none'><input type='hidden' name='csrfmiddlewaretoken' value='%s' /></div>" % (csrf_token))
+                return mark_safe("<div style='display:none'><input type='hidden' name='csrfmiddlewaretoken' value='%s' /></div>" % (csrf_token))
         else:
             # It's very probable that the token is missing because of
             # misconfiguration, so we raise a warning
@@ -22,7 +22,7 @@ def render(self, context):
             if settings.DEBUG:
                 import warnings
                 warnings.warn("A {% csrf_token %} was used in a template, but the context did not provide the value.  This is usually caused by not using RequestContext.")
-            return u''
+            return ''
 
 def fb_csrf_token(parser, token):
     return CsrfTokenNode()
diff --git a/filebrowser/templatetags/fb_pagination.py b/filebrowser/templatetags/fb_pagination.py
index 13e07a479..97460bf7c 100644
--- a/filebrowser/templatetags/fb_pagination.py
+++ b/filebrowser/templatetags/fb_pagination.py
@@ -23,24 +23,24 @@ def pagination(context):
         # If there are 10 or fewer pages, display links to every page.
         # Otherwise, do some fancy
         if paginator.num_pages <= 10:
-            page_range = range(paginator.num_pages)
+            page_range = list(range(paginator.num_pages))
         else:
             # Insert "smart" pagination links, so that there are always ON_ENDS
             # links at either end of the list of pages, and there are always
             # ON_EACH_SIDE links at either end of the "current page" link.
             page_range = []
             if page_num > (ON_EACH_SIDE + ON_ENDS):
-                page_range.extend(range(0, ON_EACH_SIDE - 1))
+                page_range.extend(list(range(0, ON_EACH_SIDE - 1)))
                 page_range.append(DOT)
-                page_range.extend(range(page_num - ON_EACH_SIDE, page_num + 1))
+                page_range.extend(list(range(page_num - ON_EACH_SIDE, page_num + 1)))
             else:
-                page_range.extend(range(0, page_num + 1))
+                page_range.extend(list(range(0, page_num + 1)))
             if page_num < (paginator.num_pages - ON_EACH_SIDE - ON_ENDS - 1):
-                page_range.extend(range(page_num + 1, page_num + ON_EACH_SIDE + 1))
+                page_range.extend(list(range(page_num + 1, page_num + ON_EACH_SIDE + 1)))
                 page_range.append(DOT)
-                page_range.extend(range(paginator.num_pages - ON_ENDS, paginator.num_pages))
+                page_range.extend(list(range(paginator.num_pages - ON_ENDS, paginator.num_pages)))
             else:
-                page_range.extend(range(page_num + 1, paginator.num_pages))
+                page_range.extend(list(range(page_num + 1, paginator.num_pages)))
     
     return {
         'page_range': page_range,
diff --git a/filebrowser/templatetags/fb_tags.py b/filebrowser/templatetags/fb_tags.py
index dd00ce3a3..2334d266b 100644
--- a/filebrowser/templatetags/fb_tags.py
+++ b/filebrowser/templatetags/fb_tags.py
@@ -50,16 +50,16 @@ def get_query_string(p, new_params=None, remove=None):
     if new_params is None: new_params = {}
     if remove is None: remove = []
     for r in remove:
-        for k in p.keys():
+        for k in list(p.keys()):
             #if k.startswith(r):
             if k == r:
                 del p[k]
-    for k, v in new_params.items():
+    for k, v in list(new_params.items()):
         if k in p and v is None:
             del p[k]
         elif v is not None:
             p[k] = v
-    return '?' + '&'.join([u'%s=%s' % (urlquote(k), urlquote(v)) for k, v in p.items()])
+    return '?' + '&'.join(['%s=%s' % (urlquote(k), urlquote(v)) for k, v in list(p.items())])
 
 
 def string_to_dict(string):
@@ -132,7 +132,7 @@ def selectable(parser, token):
     try:
         tag, filetype, format = token.split_contents()
     except:
-        raise TemplateSyntaxError, "%s tag requires 2 arguments" % token.contents.split()[0]
+        raise TemplateSyntaxError("%s tag requires 2 arguments" % token.contents.split()[0])
         
     return SelectableNode(filetype, format)
     
diff --git a/filebrowser/templatetags/fb_versions.py b/filebrowser/templatetags/fb_versions.py
index ac66e0269..d7f979a28 100644
--- a/filebrowser/templatetags/fb_versions.py
+++ b/filebrowser/templatetags/fb_versions.py
@@ -7,7 +7,7 @@
 # DJANGO IMPORTS
 from django.template import Library, Node, Variable, VariableDoesNotExist, TemplateSyntaxError
 from django.conf import settings
-from django.utils.encoding import force_unicode, smart_str
+from django.utils.encoding import force_text
 from django.core.files import File
 
 
@@ -48,7 +48,7 @@ def render(self, context):
                 source = source.path
             if isinstance(source, File):
                 source = source.name
-            source = force_unicode(source)
+            source = force_text(source)
             if FORCE_PLACEHOLDER:
                 source = PLACEHOLDER
             elif SHOW_PLACEHOLDER and not site.storage.isfile(source):
@@ -77,9 +77,9 @@ def version(parser, token):
     try:
         tag, src, version_prefix = token.split_contents()
     except:
-        raise TemplateSyntaxError, "%s tag requires 2 arguments" % token.contents.split()[0]
+        raise TemplateSyntaxError("%s tag requires 2 arguments" % token.contents.split()[0])
     if (version_prefix[0] == version_prefix[-1] and version_prefix[0] in ('"', "'")) and version_prefix.lower()[1:-1] not in VERSIONS:
-        raise TemplateSyntaxError, "%s tag received bad version_prefix %s" % (tag, version_prefix)
+        raise TemplateSyntaxError("%s tag received bad version_prefix %s" % (tag, version_prefix))
     return VersionNode(src, version_prefix)
 
 
@@ -113,7 +113,7 @@ def render(self, context):
                 source = source.path
             if isinstance(source, File):
                 source = source.name
-            source = force_unicode(source)
+            source = force_text(source)
             if FORCE_PLACEHOLDER:
                 source = PLACEHOLDER
             elif SHOW_PLACEHOLDER and not site.storage.isfile(source):
@@ -146,13 +146,13 @@ def version_object(parser, token):
         #tag, src, version_prefix = token.split_contents()
         tag, arg = token.contents.split(None, 1)
     except:
-        raise TemplateSyntaxError, "%s tag requires arguments" % token.contents.split()[0]
+        raise TemplateSyntaxError("%s tag requires arguments" % token.contents.split()[0])
     m = re.search(r'(.*?) (.*?) as (\w+)', arg)
     if not m:
-        raise TemplateSyntaxError, "%r tag had invalid arguments" % tag
+        raise TemplateSyntaxError("%r tag had invalid arguments" % tag)
     src, version_prefix, var_name = m.groups()
     if (version_prefix[0] == version_prefix[-1] and version_prefix[0] in ('"', "'")) and version_prefix.lower()[1:-1] not in VERSIONS:
-        raise TemplateSyntaxError, "%s tag received bad version_prefix %s" % (tag, version_prefix)
+        raise TemplateSyntaxError("%s tag received bad version_prefix %s" % (tag, version_prefix))
     return VersionObjectNode(src, version_prefix, var_name)
 
 
@@ -184,9 +184,9 @@ def version_setting(parser, token):
     try:
         tag, version_prefix = token.split_contents()
     except:
-        raise TemplateSyntaxError, "%s tag requires 1 argument" % token.contents.split()[0]
+        raise TemplateSyntaxError("%s tag requires 1 argument" % token.contents.split()[0])
     if (version_prefix[0] == version_prefix[-1] and version_prefix[0] in ('"', "'")) and version_prefix.lower()[1:-1] not in VERSIONS:
-        raise TemplateSyntaxError, "%s tag received bad version_prefix %s" % (tag, version_prefix)
+        raise TemplateSyntaxError("%s tag received bad version_prefix %s" % (tag, version_prefix))
     return VersionSettingNode(version_prefix)
 
 
diff --git a/filebrowser/tests/sites.py b/filebrowser/tests/sites.py
index dc8f5b9bc..445d802fd 100644
--- a/filebrowser/tests/sites.py
+++ b/filebrowser/tests/sites.py
@@ -12,13 +12,13 @@
 import os
 import sys
 import shutil
-from urllib import urlencode
+from urllib.parse import urlencode
 from types import MethodType
 
 # DJANGO IMPORTS
 from django.test import TestCase
 from django.test.client import Client
-from django.core.urlresolvers import get_resolver, get_urlconf, resolve, reverse
+from django.urls import get_resolver, get_urlconf, resolve, reverse
 
 # FILEBROWSER IMPORTS
 from filebrowser.settings import *
@@ -136,7 +136,7 @@ def test_detail(test):
     # At this moment all versions should be generated. Check that.
     for version_suffix in VERSIONS:
         path = get_version_path(test.testfile.path, version_suffix, site=test.site)
-        print 'PATH=%s' % path
+        print('PATH=%s' % path)
         test.assertTrue(test.site.storage.exists(path))
     
     # Attemp renaming the file
@@ -218,7 +218,7 @@ def setUp(self):
 def tearDown(self):
     # Delete a left-over tmp directories, if there's any
     if hasattr(self, 'tmpdir') and self.tmpdir:
-        print "Removing left-over tmp dir:", self.tmpdir.path
+        print("Removing left-over tmp dir:", self.tmpdir.path)
         self.site.storage.rmtree(self.tmpdir.path)
 
 def runTest(self):
@@ -243,7 +243,7 @@ def runTest(self):
 
 ## Create a test class for each deployed filebrowser site        
 for site in all_sites:
-    print 'Creating Test for the FileBrowser site:', site
+    print('Creating Test for the FileBrowser site:', site)
     # Create a subclass of TestCase
     testcase_class = type('TestSite_' + site, (TestCase,), {'site_name': site, 'c': Client(), 'tmpdirs': None})
     # Add setUp, tearDown, and runTest methods
diff --git a/filebrowser/widgets.py b/filebrowser/widgets.py
index 2b32120a1..ece1bea5f 100644
--- a/filebrowser/widgets.py
+++ b/filebrowser/widgets.py
@@ -19,7 +19,7 @@ class FileInput(DjangoClearableFileInput):
     initial_text = ugettext_lazy('Currently')
     input_text = ugettext_lazy('Change')
     clear_checkbox_label = ugettext_lazy('Clear')
-    template_with_initial = u'%(input)s %(preview)s'
+    template_with_initial = '%(input)s %(preview)s'
     
     def render(self, name, value, attrs=None):
         substitutions = {
@@ -29,7 +29,7 @@ def render(self, name, value, attrs=None):
             'preview': '',
             'clear_checkbox_label': self.clear_checkbox_label,
         }
-        template = u'%(input)s'
+        template = '%(input)s'
         substitutions['input'] = super(DjangoClearableFileInput, self).render(name, value, attrs)
         
         if value and hasattr(value, "url"):
@@ -53,8 +53,8 @@ class ClearableFileInput(DjangoClearableFileInput):
     input_text = ugettext_lazy('Change')
     clear_checkbox_label = ugettext_lazy('Clear')
     
-    template_with_initial = u'<p class="file-upload">%(initial_text)s: %(initial)s<span class="clearable-file-input">%(clear_template)s</span><br />%(input_text)s: %(input)s %(preview)s</p>'
-    template_with_clear = u'%(clear)s <label for="%(clear_checkbox_id)s">%(clear_checkbox_label)s</label>'
+    template_with_initial = '<p class="file-upload">%(initial_text)s: %(initial)s<span class="clearable-file-input">%(clear_template)s</span><br />%(input_text)s: %(input)s %(preview)s</p>'
+    template_with_clear = '%(clear)s <label for="%(clear_checkbox_id)s">%(clear_checkbox_label)s</label>'
 
     # template_with_initial = u'%(initial_text)s: %(initial)s %(clear_template)s<br />%(input_text)s: %(input)s'
     # template_with_clear = u'%(clear)s <label for="%(clear_checkbox_id)s">%(clear_checkbox_label)s</label>'
@@ -70,12 +70,12 @@ def render(self, name, value, attrs=None):
             'preview': '',
             'clear_checkbox_label': self.clear_checkbox_label,
         }
-        template = u'%(input)s'
+        template = '%(input)s'
         substitutions['input'] = super(DjangoClearableFileInput, self).render(name, value, attrs)
         
         if value and hasattr(value, "url"):
             template = self.template_with_initial
-            substitutions['initial'] = (u'<a target="_blank" href="%s">%s</a>' % (value.url, value))
+            substitutions['initial'] = ('<a target="_blank" href="%s">%s</a>' % (value.url, value))
             if not self.is_required:
                 checkbox_name = self.clear_checkbox_name(name)
                 checkbox_id = self.clear_checkbox_id(checkbox_name)
diff --git a/requirements.txt b/requirements.txt
index ffc1f6a61..345af4006 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,19 +1,18 @@
 # CoG application dependencies
-django==1.10.4
-django-grappelli==2.8.1
+django==2.2.24
+django-grappelli>2.13,<2.15
 #django-openid-auth==0.7', # must be installed independently from fork
-sqlalchemy>=1.0.11,<1.3
+sqlalchemy>=1.3,<1.4
 south==1.0.2
-psycopg2>=2.5.2,<2.7
-python-openid==2.2.5
-passlib==1.6.5
-pysqlite==2.8.1
-django-contrib-comments==1.6.2
-oauth2client==2.0.1
-globusonline-transfer-api-client==0.10.18
+psycopg2==2.8.4
+python3-openid==3.1.0
+passlib==1.7.2
+django-contrib-comments==1.9.1
+oauth2client==4.1.3
+globus-sdk==1.8.0
 #'pillow==3.1.0', # pre-requisite: must be installed with --use-wheel on MAC-OSX
-django-simple-captcha==0.5.1
-html5lib==1.0b8
-bleach==1.4.2
-python-magic==0.4.12
-esgfpid==0.7.10
+django-simple-captcha==0.5.12
+html5lib==1.0.1
+bleach>=3.3.0
+python-magic==0.4.15
+#esgfpid==0.7.14  # Used for datacart PIDs.  Currently not used in production.
diff --git a/resources/scripts/configure_search.py b/resources/scripts/configure_search.py
index cf43083f3..93271a64c 100644
--- a/resources/scripts/configure_search.py
+++ b/resources/scripts/configure_search.py
@@ -1,5 +1,5 @@
 # Python script to configure off-band a project advanced search
-import sys, os, ConfigParser
+import sys, os, configparser
 
 sys.path.append( os.path.abspath(os.path.dirname('.')) )
 os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'
@@ -7,7 +7,7 @@
 from cog.config.search import read_config
 #from django.conf import settings
 
-print 'Upgrading COG'
+print('Upgrading COG')
 
 # read search configurations
 configs = { 'StandardDistribution': 'cog/config/search/standard_distribution.cfg',
diff --git a/resources/scripts/fix_broken_links.py b/resources/scripts/fix_broken_links.py
index c0a825ec2..406800add 100644
--- a/resources/scripts/fix_broken_links.py
+++ b/resources/scripts/fix_broken_links.py
@@ -19,7 +19,7 @@
 for post in Post.objects.all():
     
     if BAD_LINK in post.body:
-        print "Found bad link at URL: %s" % post.url
+        print("Found bad link at URL: %s" % post.url)
         post.body = post.body.replace(BAD_LINK, GOOD_LINK)
         post.save()
         
diff --git a/resources/scripts/insert_esgf_user.py b/resources/scripts/insert_esgf_user.py
index 6daf1f098..3e4f11e20 100644
--- a/resources/scripts/insert_esgf_user.py
+++ b/resources/scripts/insert_esgf_user.py
@@ -28,11 +28,11 @@
 openid = ''
 for userOpenID in user.useropenid_set.all():
     openid = userOpenID.claimed_id
-    print 'User openid=%s' % openid
+    print('User openid=%s' % openid)
 
 # verify user was inserted
 esgfUser2 = esgfDatabaseManager.getUserByOpenid( openid )
-print "Retrieved user with openid=%s" % esgfUser2.openid
+print("Retrieved user with openid=%s" % esgfUser2.openid)
 
 # cleanup tgis execution
 user.delete()
\ No newline at end of file
diff --git a/resources/scripts/migrate_roles.py b/resources/scripts/migrate_roles.py
index 66343912d..7610e8463 100644
--- a/resources/scripts/migrate_roles.py
+++ b/resources/scripts/migrate_roles.py
@@ -14,7 +14,7 @@
 # loop over users
 for user in User.objects.all():
     
-    print 'Processing user=%s' % user
+    print('Processing user=%s' % user)
     
     # FIXME
     #if user.last_name=='Cinquini':
@@ -28,7 +28,7 @@
                 user.groups.remove( ugroup )
                 # add 'contributor' group
                 cgroup = project.getContributorGroup()
-                print '\tUser %s: changing group %s to %s' % (user, ugroup, cgroup)
+                print('\tUser %s: changing group %s to %s' % (user, ugroup, cgroup))
                 user.groups.add( cgroup )
                 user.save()
             except Project.DoesNotExist:
@@ -37,7 +37,7 @@
     # delete obsolete Permission objects
     for permission in user.user_permissions.all():
         if 'Admin Permission' in permission.name or 'User Permission' in permission.name:
-            print '\tUser: %s deleting permission: %s' % (user, permission)
+            print('\tUser: %s deleting permission: %s' % (user, permission))
             user.user_permissions.remove(permission)
             user.save()
             permission.delete()
\ No newline at end of file
diff --git a/resources/scripts/migrate_users.py b/resources/scripts/migrate_users.py
index 03015ae89..cbe0af392 100644
--- a/resources/scripts/migrate_users.py
+++ b/resources/scripts/migrate_users.py
@@ -64,7 +64,7 @@
                         if settings.ESGF_HOSTNAME in esgfUser.openid and user.username in esgfUser.openid:
                             if not UserOpenID.objects.filter(claimed_id=esgfUser.openid).exists():
                                 openid = UserOpenID.objects.create(user=user, claimed_id=esgfUser.openid, display_id=esgfUser.openid)
-                                print 'Assigned ESGF openid=%s to CoG user=%s' % (openid.claimed_id, user)
+                                print('Assigned ESGF openid=%s to CoG user=%s' % (openid.claimed_id, user))
                                 found = True
                     if not found:
                         esgfDatabaseManager.insertUser(userp)
diff --git a/resources/scripts/send_email.py b/resources/scripts/send_email.py
index 044aee449..c37e93fa0 100644
--- a/resources/scripts/send_email.py
+++ b/resources/scripts/send_email.py
@@ -36,11 +36,11 @@ def __init__ (self, toAddress, subject, message, fromAddress=EMAIL_SENDER, mime_
     def run(self):
         
         #print "From: %s" % self.fromAddress
-        print "To: %s" % self.toAddress
-        print 'From: %s' % self.fromAddress 
-        print "Subject: %s" % self.subject
-        print "Message: %s" % self.message
-        print "Mime Type: %s" % self.mime_type
+        print("To: %s" % self.toAddress)
+        print('From: %s' % self.fromAddress) 
+        print("Subject: %s" % self.subject)
+        print("Message: %s" % self.message)
+        print("Mime Type: %s" % self.mime_type)
         
         # use local mail server
         #toUser.email_user(subject, message, from_email=fromAddress)
@@ -59,7 +59,7 @@ def run(self):
             s.login(EMAIL_USERNAME, EMAIL_PASSWORD)
         s.sendmail(self.fromAddress, [self.toAddress], msg.as_string())
         s.quit()
-        print 'Email sent.'
+        print('Email sent.')
 
 
 if __name__ == '__main__':
diff --git a/settings.py b/settings.py
index 1b592a1e4..be54b3008 100644
--- a/settings.py
+++ b/settings.py
@@ -16,7 +16,7 @@
 from cog.site_manager import siteManager
 from cog.constants import SECTION_ESGF, SECTION_PID
 
-COG_VERSION = 'v3.15.4'
+COG_VERSION = 'v4.0.1'
 
 SITE_NAME = siteManager.get('SITE_NAME', default='Local CoG')
 SITE_DOMAIN = siteManager.get('SITE_DOMAIN', default='localhost:8000')
@@ -44,23 +44,23 @@
 else:
     DEBUG = False
 ALLOWED_HOSTS = siteManager.get('ALLOWED_HOSTS', default=SITE_DOMAIN).split(",")
-print 'Using DEBUG=%s ALLOWED_HOSTS=%s' % (DEBUG, ALLOWED_HOSTS)
+print('Using DEBUG=%s ALLOWED_HOSTS=%s' % (DEBUG, ALLOWED_HOSTS))
 IDP_WHITELIST = siteManager.get('IDP_WHITELIST', default=None)
-print 'Using IdP whitelist(s): %s' % IDP_WHITELIST
+print('Using IdP whitelist(s): %s' % IDP_WHITELIST)
 KNOWN_PROVIDERS = siteManager.get('KNOWN_PROVIDERS', default=None)
-print 'Using list of known Identity Providers: %s' % KNOWN_PROVIDERS
+print('Using list of known Identity Providers: %s' % KNOWN_PROVIDERS)
 PEER_NODES = siteManager.get('PEER_NODES', default=None)
 USE_CAPTCHA = str2bool(siteManager.get('USE_CAPTCHA', default='True'))
-print 'Using list of ESGF/CoG peer nodes from: %s' % PEER_NODES
+print('Using list of ESGF/CoG peer nodes from: %s' % PEER_NODES)
 # DEVELOPMENT/PRODUCTION server switch
 PRODUCTION_SERVER = str2bool(siteManager.get('PRODUCTION_SERVER', default='False'))
-print 'Production server flag=%s' % PRODUCTION_SERVER
+print('Production server flag=%s' % PRODUCTION_SERVER)
 
 WPS_ENDPOINT = siteManager.get('WPS_ENDPOINT', default=None);
 # Fields that will be added to the query string
 WPS_FIELDS = siteManager.get('WPS_FIELDS', default='index_node').split(',');
 WPS_DATACART = str2bool(siteManager.get('WPS_DATACART', default='False'))
-print 'WPS endpoint: %s, datacart enabled: %s, fields: %s' % (WPS_ENDPOINT, WPS_DATACART, ','.join(WPS_FIELDS))
+print('WPS endpoint: %s, datacart enabled: %s, fields: %s' % (WPS_ENDPOINT, WPS_DATACART, ','.join(WPS_FIELDS)))
 
 # FIXME
 # ESGF specific settings
@@ -172,7 +172,7 @@
 # must be writable by web server
 PROJECT_CONFIG_DIR = os.path.join(MEDIA_ROOT, 'config')
 
-print 'Loading custom templates from directories: %s, %s' % (MYTEMPLATES, MYMEDIA)
+print('Loading custom templates from directories: %s, %s' % (MYTEMPLATES, MYMEDIA))
 
 # Make this unique, and don't share it with anybody.
 #SECRET_KEY = 'yb@$-bub$i_mrxqe5it)v%p=^(f-h&x3%uy040x))19g^iha&#'
@@ -204,7 +204,7 @@
     },
 ]
 
-MIDDLEWARE_CLASSES = (
+MIDDLEWARE = (
     'django.middleware.common.CommonMiddleware',
     'django.middleware.clickjacking.XFrameOptionsMiddleware',
     'django.contrib.sessions.middleware.SessionMiddleware',
diff --git a/setup.py b/setup.py
index eca7d56a4..0177d4b7f 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,7 @@ def read(fname):
 
 setup(
     name = "cog",
-    version = "3.11",
+    version = "4.0.1",
     author = "CoG Development Team",
     author_email = "cog_support@list.woc.noaa.gov",
     description = ("Earth System CoG: web interface for the Earth System Grid Federation"),
diff --git a/urls.py b/urls.py
index abde4229a..89bc4acde 100644
--- a/urls.py
+++ b/urls.py
@@ -12,15 +12,15 @@
 urlpatterns = [
                        
     # forbidden extensions (case-insensitive)
-    url(r'(?i).*\.asp\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.aspx\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.cfm\/?$', HttpResponseNotFound),
-    url(r'.*\.cgi\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.jsp\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.php\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.php3\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.pl\/?$', HttpResponseNotFound),
-    url(r'(?i).*\.shtml\/?$', HttpResponseNotFound),
+    url(r'.*\.asp\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.aspx\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.cfm\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.cgi\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.jsp\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.php\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.php3\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.pl\/?$(?i)', HttpResponseNotFound),
+    url(r'.*\.shtml\/?$(?i)', HttpResponseNotFound),
     
     url(r'^robots\.txt$', django.views.generic.TemplateView.as_view(template_name='robots.txt', content_type='text/plain'), name='robots.txt'),
                                                       
@@ -32,11 +32,11 @@
     
     # Filebrowser Admin pages
     #(r'^filebrowser/', include('filebrowser.urls')),
-    url(r'^admin/filebrowser/', include(site.urls)),
+    url(r'^admin/filebrowser/', site.urls),
 
     # Administrator application
     #(r'^admin/doc/', include('django.contrib.admindocs.urls')),
-    url(r'^admin/', include(admin.site.urls)),
+    url(r'^admin/', admin.site.urls),
             
     # django-simple-captcha
     url(r'^captcha/', include('captcha.urls')),