#!/usr/bin/env python3
from functools import wraps
import inspect

def argparse_compatible(func):
    """Decorator that enables calling a function with its arguments or using an argparse.Namespace object.
    For example, the function

    @argparse_compatible
    def f(a, b, c):
        return None

    can be called via

    f(a, b, c)

    or via

    parser = argparse.ArgumentParser()
    parser.add_argument("-a")
    parser.add_argument("-b")
    parser.add_argument("-c")
    args = parser.parse_args()

    f(args)
    """
    @wraps(func)
    def wrapper(*args, **kwargs):
        if len(args) == 1 and type(args[0]) == argparse.Namespace:
            expected_args = inspect.signature(func).parameters.keys()
            args = {arg: getattr(args[0], arg) for arg in expected_args if hasattr(args[0], arg)}
            return func(**args)
        else:
            return func(*args, **kwargs)

    return wrapper