Decorators in Python

A decorator is a function that takes another function and extends its behavior without modifying it directly. They rely on closures to keep a reference to the original function.

import functools

def log(func):
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        print(f"calling {func.__name__}")
        return func(*args, **kwargs)
    return wrapper

@log
def soma(a, b):
    return a + b

functools.wraps preserves the name and docstring of the decorated function.