Python Decorator functools.wrap

######################################################

# Decorators

# use of functools.wraps

# The @functools.wraps decorator uses the function functools.update_wrapper() to update special attributes

# like __name__ and __doc__ that are used in the introspection.

######################################################

import functools

def decorator1(f):

    print('inside decorator1')

    def wrap(*args, **kwargs):

        f(*args, **kwargs)

    return wrap

@decorator1

def test_decorator1_func():

    """ test_decorator1_func documentation """

    print('inside test_decorator1_func')

def decorator2(f):

    print('inside decorator2')

    def wrap(*args, **kwargs):

        f(*args, **kwargs)

    wrap.__name__ = f.__name__

    wrap.__doc__ = f.__doc__

    return wrap

@decorator2

def test_decorator2_func():

    """ test_decorator2_func documentation """

    print('inside test_decorator2_func')

def decorator3(f):

    print('inside decorator3')

    @functools.wraps(f)

    def wrap(*args, **kwargs):

        f(*args, **kwargs)

    return wrap

@decorator3

def test_decorator3_func():

    """ test_decorator3_func documentation """

    print('inside test_decorator3_func')

if __name__ == '__main__':

    print('------------------------------------')

    # print(help(test_decorator1_func))

    print(test_decorator1_func.__name__)     # wrap

    print(test_decorator1_func.__doc__)      # None

    print(test_decorator1_func.__closure__)  # (<cell at 0x1064d0b28: function object at 0x1064ebe18>,)

    print('------------------------------------')

    # Using functools

    # print(help(test_decorator2_func))

    print(test_decorator2_func.__name__)     # test_decorator2_func

    print(test_decorator2_func.__doc__)      # test_decorator2_func

    print(test_decorator2_func.__closure__)  # (<cell at 0x1064d0b28: function object at 0x10654bc80>,)

    print('------------------------------------')

    # Using functools - this will achieve same as test_decorator2_func

    # print(help(test_decorator3_func))

    print(test_decorator3_func.__name__)     # test_decorator3_func

    print(test_decorator3_func.__doc__)      # test_decorator3_func documentation

    print(test_decorator3_func.__closure__)  # (<cell at 0x10344df18: function object at 0x1034e0d08>,)

    print('------------------------------------')