Python · Decorators

A decorator's wrapper is written as def wrapper(*args, **kwargs): and calls fn(*args, **kwargs). Why both the */** in the signature AND in the call?

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More in Decorators

What does @deco written above a function definition actually do to the name?

What does this print? ```python def with_timing(fn): def wrapper(*a, **k): return fn(*a, **k) return wrapper @with_timing def nap(): """sleep""" print(nap.__name__) ```

What does functools.wraps do, and where do you put it?

What does this print? ```python def a(f): def w(): print("a"); f() return w def b(f): def w(): print("b"); f() return w @a @b def g(): print("g") g() ```

@a then @b above a function is equivalent to which single assignment?

Your decorator's wrapper works, but the decorated function's call returns None even though the original returns a value. What's the bug?

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