Tell me about decorators in Python: what is this pattern and how to implement a decorator with arguments?

A decorator in Python is a design pattern that allows you to wrap a function or method, adding additional behavior without modifying the original code.

The simplest decorator is a function that takes another function and returns a new function:

def decorator(func):
    def wrapper(*args, **kwargs):
        print("Before calling the function")
        result = func(*args, **kwargs)
        print("After calling the function")
        return result
    return wrapper

@decorator
def say_hello(name):
    print(f"Hello, {name}!")

say_hello("World")

To create a decorator with arguments, an additional level of nesting is needed:

def repeat(times):
    def decorator(func):
        def wrapper(*args, **kwargs):
            for _ in range(times):
                func(*args, **kwargs)
        return wrapper
    return decorator

@repeat(3)
def greet(name):
    print(f"Hello, {name}!")

greet("Anna")

Here, repeat is a function that takes an argument times and returns a decorator. This approach allows parameterizing the behavior of the decorator.