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Modern tooling

uv, ruff, pyproject.toml, packaging, and current Python project workflows.

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Modern tooling medium

How to set up mypy strict mode in Python

Demonstrates how to configure and run mypy in strict mode to enforce full type annotation coverage across a Python project.

mypy type-hints strict-mode
Python 
from typing import Dict, Optional


def describe_user(name: str, age: int, email: Optional[str] = None) -> Dict[str, object]:
    """Build a user description dictionary with strict type annotations."""
    user: Dict[str, object] = {"name": name, "age": age}
    if email is not None:
        user["email"] = email
    …
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