@wraps preserve attributes of the original function, otherwise attributes
of the decorated function will be replaced by wrapper function. For example
Without @wraps
>>> def decorator(func):
... def wrapper(*args, **kwargs):
... print('wrap function')
... return func(*args, **kwargs)
... return wrapper
...
>>> @decorator
... def example(*a, **kw):
... pass
...
>>> example.__name__ # attr of function lose
'wrapper'With @wraps
>>> from functools import wraps
>>> def decorator(func):
... @wraps(func)
... def wrapper(*args, **kwargs):
... print('wrap function')
... return func(*args, **kwargs)
... return wrapper
...
>>> @decorator
... def example(*a, **kw):
... pass
...
>>> example.__name__ # attr of function preserve
'example'