What is functools.wraps?

functools.wraps is a decorator for wrapper functions. It copies metadata from the original function onto the wrapper (__name__, __doc__, __module__, __annotations__, and more) and sets __wrapped__ so introspection can reach the original.

Without wraps, decorated functions look like wrapper, which breaks docs, debugging, and some libraries.

from functools import wraps

def noisy(fn):
    @wraps(fn)
    def wrapper(*args, **kwargs):
        print(f"calling {fn.__name__}")
        return fn(*args, **kwargs)
    return wrapper

@noisy
def add(a, b):
    """Add two numbers."""
    return a + b

print(add.__name__)   # add  (not wrapper)
print(add.__doc__)    # Add two numbers.
print(add(2, 3))
print(add.__wrapped__(2, 3))  # original

Interview tip: Always mention @wraps(fn) when writing decorator examples; interviewers look for that habit.