Garbage collection in Python is the process of automatically reclaiming memory
that is no longer in use by the program. This is essential for managing memory
and preventing memory leaks, which can lead to inefficient use of resources and
potentially crash the program.
Python's garbage collection system helps manage memory automatically, allowing
developers to focus on writing code without worrying too much about memory
management.
Python is dynamic, meaning its behavior is largely determined at runtime rather
than at compile time. This includes:
- Interpreted Language: Python is executed line-by-line at runtime by the
interpreter, which allows for quick testing and debugging without the need for
compilation. - Dynamic Typing: Variables can change type as the program executes, without the
need for explicit declarations. - Dynamic Memory Management: Automatic handling of memory allocation and garbage
collection, relieving developers from manual memory management. - Dynamic Attribute Creation: Attributes can be added, modified, or deleted from
objects at runtime, providing flexibility and extensibility. - Run-time Reflection: Ability to inspect and modify the program structure at
runtime, such as accessing object types and attributes.
Python Enhancement Proposals (PEPs) are design documents providing information
to the Python community, or describing a new feature for Python or its processes
or environment. PEPs are intended to be the primary mechanism for proposing
major new features, collecting community input on an issue, and documenting the
design decisions that have gone into Python.
Key points:
- Proposals for Changes: PEPs propose changes to the Python language, libraries,
or processes. They can range from small enhancements to major new features. - Community Involvement: PEPs are open to community review and feedback,
allowing Python developers to discuss and refine the proposals. - Standardization: Accepted PEPs provide a standardized way of implementing new
features or changes, ensuring consistency across the Python ecosystem. - Documentation: PEPs serve as detailed documentation of the design decisions
and rationale behind changes or new features in Python.
Example PEPs:
- PEP 8: Style Guide for Python Code – Provides guidelines for writing readable
and consistent Python code. - PEP 20: The Zen of Python – A collection of aphorisms that capture the philosophy of Python.
- PEP 484: Type Hints – Introduces a standard for adding type hints to Python
code.
Summary:
PEPs are essential to the evolution of Python, enabling organized and
well-documented changes that incorporate community feedback and expertise. They
help ensure that Python remains a robust, adaptable, and widely-used programming
language.
Python uses a form of a semantic versioning system to manage and identify
different releases of the language. The version numbers follow a structured
format to convey information about the nature of changes in each release.
Python version numbers are typically represented in the format: MAJOR.MINOR.MICRO
- MAJOR: Indicates significant changes that may include backward-incompatible
changes. Major version changes introduce new language features or substantial
changes to existing features.
Example: Python 2.x to Python 3.x
- MINOR: Represents smaller, backward-compatible enhancements and improvements.
Minor version updates may include new features, optimizations, and other
enhancements while maintaining backward compatibility with the previous major
version.
Example: Python 3.8 to Python 3.9
MICRO: Denotes maintenance releases that include bug fixes and minor
improvements. These updates focus on addressing issues without introducing new
features or changes that might affect backward compatibility.
Example: Python 3.9.1 to Python 3.9.2
Python 3.9.2:
- MAJOR: 3 (Introduces new language features)
- MINOR: 9 (Backward-compatible improvements)
- MICRO: 2 (Bug fixes and minor improvements)
This structured versioning system helps developers understand the nature and
scope of changes in each release, enabling better planning for upgrades and
compatibility considerations.