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functools.wraps

decorators

Copies the metadata of the wrapped function (__name__, __doc__, __annotations__) onto the wrapper. A must when writing decorators.

Syntax

@functools.wraps(wrapped)

Skip it and your decorated function starts lying about itself: help() and __name__ report wrapper, doctests stop being collected, and anything keyed by function name — docs generators, registries — quietly breaks. Note that wraps only repairs introspection: the callable is still wrapper(*args, **kwargs); inspect.signature merely follows the __wrapped__ link it sets to report the original signature.

Examples

from functools import wraps
def my_decorator(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        return func(*args, **kwargs)
    return wrapper
@my_decorator
def greet(name):
    """Say hello."""
    return f'Hello, {name}'
print(greet.__name__)  # → greet
print(greet.__doc__)  # → Say hello.
print(greet('Alice'))  # → Hello, Alice
print(greet.__wrapped__)  # → ? repr функции содержит адрес

functools.wraps

Syntax

Examples

See also