Pythonic idioms, PEP 8 standards, type hints, and best practices for building robust, efficient, and maintainable Python applications. Use when writing or reviewing Python code and idiomatic structure, typing, or PEP 8 is in question.

Python Development Patterns Idiomatic Python patterns and best practices for building robust, efficient, and maintainable applications. When to Activate Writing new Python code Reviewing Python code Refactoring existing Python code Designing Python packages/modules Core Principles 1. Readability Counts Python prioritizes readability. Code should be obvious and easy to understand. 2. Explicit is Better Than Implicit Avoid magic; be clear about what your code does. 3. EAFP Easier to Ask Forgiveness Than Permission Python prefers exception handling over checking conditions. Type Hints Basic Type Annotations Modern Type Hints (Python 3.9+) Type Aliases and TypeVar Protocol Based Duck Typing Error Handling Patterns Specific Exception Handling Exception Chaining Custom Exception Hierarchy Context Managers Resource Management Custom Context Managers Context Manager Classes Comprehensions and Generators List Comprehensions Generator Expressions Generator Functions Data Classes and Named Tuples Data Classes Data Classes with Validation Named Tuples Decorators Function Decorators Parameterized Decorators Class Based Decorators Concurrency Patterns Threading for I/O Bound Tasks Multiprocessing for CPU Bound Tasks Async/Await for Concurrent I/O Package Organization Standard Project Layout Import Conventions init .py for Package Exports Memory and Performance Using slots for Memory Efficiency Generator for Large Data Avoid String Concatenation in Loops Python Tooling Integration Essential Commands pyproject.toml Configuration Quick Reference: Python Idioms Idiom Description EAFP Easier to Ask Forgiveness than Permission Context managers Use with for resource management List comprehensions For simple transformations Generators For lazy evaluation and large datasets Type hints Annotate function signatures Dataclasses For data containers with auto generated methods slots For memory optimization f strings For string formatting (Python 3.6+) pathlib.Path For path operations (Python 3.4+) enumerate For index element pairs in loops Anti Patterns to Avoid Remember : Python code should be readable, explicit, and follow the principle of least surprise. When in doubt, prioritize clarity over cleverness.

python-patterns