diff --git a/sandbox/grist/dropdown_condition.py b/sandbox/grist/dropdown_condition.py
index a031d4b4f5..30ef271dbf 100644
--- a/sandbox/grist/dropdown_condition.py
+++ b/sandbox/grist/dropdown_condition.py
@@ -1,5 +1,6 @@
 import json
 import logging
+import usertypes
 
 from predicate_formula import NamedEntity, parse_predicate_formula_json, TreeConverter
 import predicate_formula
@@ -38,12 +39,7 @@ def perform_dropdown_condition_renames(useractions, renames):
       continue
 
     # Find out what table this column refers to and belongs to.
-    if col.type.startswith("Ref:"):
-      ref_table_id = col.type[4:]
-    elif col.type.startswith("RefList:"):
-      ref_table_id = col.type[8:]
-    else:
-      ref_table_id = None
+    ref_table_id = usertypes.get_referenced_table_id(col.type)
     self_table_id = col.parentId.tableId
 
     def renamer(subject):
diff --git a/sandbox/grist/usertypes.py b/sandbox/grist/usertypes.py
index d617b927f7..d599a22273 100644
--- a/sandbox/grist/usertypes.py
+++ b/sandbox/grist/usertypes.py
@@ -63,6 +63,13 @@ def wrapper(method):
     return method
   return wrapper
 
+def get_referenced_table_id(col_type):
+  if col_type.startswith("Ref:"):
+    return col_type[4:]
+  if col_type.startswith("RefList:"):
+    return col_type[8:]
+  return None
+
 
 def ifError(value, value_if_error):
   """