What are the best practices for using *args and **kwargs in Python?

What are the best practices for using *args and **kwargs in Python?

Using *args and **kwargs allows you to pass a variable number of arguments to a function. Best practices include: 1. Use *args for non-keyword arguments and **kwargs for keyword arguments. 2. Keep the function signature clear and document the expected arguments. 3. Avoid overusing them to maintain readability.

Can you give me an example of how to use them?

Sure! Here's a simple example:

def example_function(*args, **kwargs):
    print('Positional arguments:', args)
    print('Keyword arguments:', kwargs)

example_function(1, 2, 3, name='Alice', age=30)

This will output:

Positional arguments: (1, 2, 3)
Keyword arguments: {'name': 'Alice', 'age': 30}

Are there any performance considerations I should be aware of?

Yes, using *args and **kwargs can introduce a slight overhead due to the flexibility they provide. If performance is critical, consider using explicit arguments instead. However, for most applications, the difference is negligible.

What about type hints? How can I use them with *args and **kwargs?

You can use type hints with *args and **kwargs by specifying the types as follows:

def example_function(*args: int, **kwargs: str) -> None:
    pass

This indicates that *args should be integers and **kwargs should be strings.