What are decorators in Python and how do they work?

What are decorators in Python and how do they work?

Decorators in Python are functions that modify the behavior of another function. They allow you to wrap another function to extend its behavior without permanently modifying it.

Can you give me an example of a simple decorator?

Sure! Here's a simple decorator that prints 'Hello' before calling the function:

def my_decorator(func):
    def wrapper():
        print('Hello')
        func()
    return wrapper

@my_decorator
def say_hello():
    print('World!')

say_hello()  # Output: Hello
              #         World!

What is the purpose of the @ symbol in decorators?

The @ symbol is a syntactic sugar in Python that allows you to apply a decorator to a function in a cleaner way. It essentially replaces the need to call the decorator function explicitly.

Can decorators take arguments?

Yes, decorators can take arguments. You would need to define a decorator factory that returns a decorator. Here's an example:

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

@repeat(3)
def greet(name):
    print(f'Hello {name}')

greet('Alice')  # Output: Hello Alice (3 times)