Python Best Practices

PEP 8 Style Guide

Code Formatting

• Indentation (4 spaces)
• Maximum line length (79 characters)
• Blank lines
• Imports organization
• Whitespace usage
• Naming conventions (snake_case for functions/variables, PascalCase for classes)

Code Organization

• Module-level dunder names
• Function and class definitions order
• Docstring conventions

Virtual Environments

Creating Virtual Environments

• venv module
• virtualenv tool
• conda environments
• Activating and deactivating environments

Best Practices

• One virtual environment per project
• Including/excluding from version control
• Requirements files
• Environment isolation

Package Management

pip

• Installing packages
• Requirements files (requirements.txt)
• Installing from requirements
• Upgrading packages
• Uninstalling packages

Poetry

• Project initialization
• Adding dependencies
• pyproject.toml file
• Lock files
• Publishing packages

Other Tools

• pipenv
• conda
• pip-tools

Testing with pytest

Writing Tests

• Test function naming
• Assert statements
• Test organization
• Fixtures
• Parametrized tests

Running Tests

• Running specific tests
• Verbose output
• Coverage reports
• Test discovery

Advanced Features

• Mocking with unittest.mock
• Pytest fixtures
• Pytest plugins
• Test configuration

Code Quality Tools

Linting

• flake8
• pylint
• black (code formatter)
• isort (import sorter)

Type Checking

• mypy
• pyright
• Type stubs

Documentation

• Docstrings (Google style, NumPy style)
• Sphinx for documentation generation
• Type hints in docstrings

Practice Questions

Test your understanding with the questions in the interactive quiz below (when available).

Resources

• PEP 8 Style Guide: https://pep8.org/
• Python Packaging Guide: https://packaging.python.org/
• pytest Documentation: https://docs.pytest.org/
• Real Python Testing Guide: https://realpython.com/python-testing/