python.mdc

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description: 
globs: **/*.py
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description: Python best practices and patterns for modern software development
globs: **/*.py, src/**/*.py, tests/**/*.py
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# Python Best Practices

## Project Structure
- Use src-layout with `src/your_package_name/`
- Place tests in `tests/` directory and keep it flat
- Keep configuration in `config/` or as environment variables
- Store requirements in  `pyproject.toml`
- Use `templates/` for Jinja2 templates

## Code Style
- Follow Ruff code formatting
- Use isort for import sorting
- Follow PEP 8 naming conventions:
  - snake_case for functions and variables
  - PascalCase for classes
  - UPPER_CASE for constants
- Maximum line length of 88 characters (Black default)
- Use absolute imports over relative imports

## Type Hints
- Use type hints for all function parameters and returns
- Import types from `typing` module
- Use `Optional[Type]` instead of `Type | None`
- Use `TypeVar` for generic types
- Define custom types in `types.py`
- Use `Protocol` for duck typing

## Testing
- Use pytest for testing
- Implement proper fixtures
- Use proper mocking with pytest-mock
- Test all error scenarios

## Performance
- Use proper connection pooling when needed
- Use background tasks for heavy operations
- Monitor application performance

## Error Handling
- Create custom exception classes
- Use proper try-except blocks
- Implement proper logging
- Return proper error responses
- Handle edge cases properly
- Use proper error messages

## Documentation
- Use Google-style docstrings
- Document all public APIs
- Keep README.md updated
- Use proper inline comments
- Document using markdown in `docs` directory

## Development Workflow
- Follow TDD methology and write acceptence tests
- Use pytest extensively to test your code
- Use virtual environments (venv)
- Use proper Git workflow
- Follow semantic versioning
- Use proper CI/CD practices
- Implement proper logging

## Dependencies
- Pin dependency versions
- Separate dev dependencies
- Use proper package versions
- Regularly update dependencies
- Check for security vulnerabilities
- Use uv for venv and dependency management