Python convert args to kwargs

Question

I am writing a decorator that needs to call other functions prior to call of the function that it is decorating. The decorated function may have positional arguments, but the f

Answer 1

Nadia's answer is correct, but I feel like a working demo of that answer is useful.

def decorator(func):
    def wrapped_func(*args, **kwargs):
        kwargs.update(zip(func.__code__.co_varnames, args))
        print(kwargs)
        return func(**kwargs)
    return wrapped_func

@decorator
def thing(a,b):
    return a+b

Given this decorated function, the following calls return the appropriate answer:

thing(1, 2)  # prints {'a': 1, 'b': 2}  returns 3
thing(1, b=2)  # prints {'b': 2, 'a': 1}  returns 3
thing(a=1, b=2)  # prints {'a': 1, 'b': 2}  returns 3

Note however that things start getting weird if you start nesting decorators because the decorated function now no longer takes a and b, it takes args and kwargs:

@decorator
@decorator
def thing(a,b):
    return a+b

Here thing(1,2) will print {'args': 1, 'kwargs': 2} and error with TypeError: thing() got an unexpected keyword argument 'args'