What are the best practices for using mypy annotations?

What are the best practices for using mypy annotations?

The best practices for using mypy annotations include being consistent, using type hints for function parameters and return types, and leveraging type aliases for complex types.

Can you give me an example of a function with type annotations?

Sure! Here's a simple example:

def add_numbers(a: int, b: int) -> int:
    return a + b

How do I handle optional types in mypy?

You can use the Optional type from the typing module. For example:

from typing import Optional

def get_name(user_id: int) -> Optional[str]:
    # logic to get name
    return None  # if not found

What about using mypy with third-party libraries?

You can use type stubs or check if the library provides type hints. If not, you can create your own stubs.