Demo of decorators usage in Python

decorators.py

def function_decorator(f):
    print('decorating {}'.format(f.__name__))
    def wrapper(*args, **kwargs):
        print('calling {}'.format(f.__name__))
    return wrapper


@function_decorator
def decorated_function():
    print('actual call')


decorated_function()
decorated_function()


class class_decorator():
    def __init__(self, clazz):
        self.clazz = clazz
        print('decorating {}'.format(clazz))

    def __call__(self):
        print('creating an instance of {}'.format(self.clazz))
        return self.clazz()


@class_decorator
class DecoratedClass():
    @function_decorator
    def decorated_method(self):
        print('called class decorated method')

dc = DecoratedClass()
dc.decorated_method()


@class_decorator
def class_decorated_function():
    print('actual call')

class_decorated_function()