python-development

Python Development

// Description: Modern Python development practices with type hints, testing, and AI-friendly patterns // Recommended Globs: **/*.py, **/pyproject.toml, **/requirements.txt, */.env

Project Structure

project_name/
├── src/
│   └── project_name/
│       ├── __init__.py
│       ├── models/
│       ├── services/
│       ├── controllers/
│       └── utils/
├── tests/
│   ├── __init__.py
│   ├── conftest.py
│   ├── unit/
│   └── integration/
├── docs/
├── .env
├── .env.example
├── .gitignore
├── pyproject.toml
├── README.md
└── requirements.txt

Type Annotations

Always use type hints for functions and classes:

from typing import Optional, List, Dict, Any, TypeVar, Generic
from typing_extensions import TypedDict  # For Python <3.8

T = TypeVar('T')

class DataResponse(TypedDict):
    success: bool
    data: Dict[str, Any]
    error: Optional[str]

class Repository(Generic[T]):
    """Generic repository pattern implementation.

    Args:
        model: The model class this repository handles

    Attributes:
        model_class: Stored model class reference
    """

    def __init__(self, model: type[T]) -> None:
        self.model_class = model

    async def find_by_id(self, id: str) -> Optional[T]:
        """Retrieve an entity by its ID.

        Args:
            id: The unique identifier of the entity

        Returns:
            Optional[T]: The found entity or None
        """
        # Implementation
        ...

Testing with Pytest

Use pytest fixtures and type annotations in tests:

from typing import TYPE_CHECKING, AsyncGenerator
import pytest
from httpx import AsyncClient

if TYPE_CHECKING:
    from _pytest.capture import CaptureFixture
    from _pytest.fixtures import FixtureRequest
    from _pytest.logging import LogCaptureFixture
    from _pytest.monkeypatch import MonkeyPatch
    from pytest_mock.plugin import MockerFixture

@pytest.fixture
async def client() -> AsyncGenerator[AsyncClient, None]:
    """Create async test client.

    Yields:
        AsyncClient: The test client instance
    """
    async with AsyncClient() as client:
        yield client

@pytest.mark.asyncio
async def test_create_user(
    client: AsyncClient,
    mocker: MockerFixture,
    caplog: LogCaptureFixture,
) -> None:
    """Test user creation endpoint.

    Args:
        client: The test client
        mocker: Pytest mocker fixture
        caplog: Pytest log capture fixture
    """
    response = await client.post('/users', json={
        'username': 'test_user',
        'email': '[email protected]'
    })
    
    assert response.status_code == 201
    assert 'User created successfully' in caplog.text