Dependency injection in python

inject.py

import inspect
from functools import wraps

def inject(function):
    @wraps(function)
    def inner(**kwargs):
        original_args_list = inspect.getargspec(function).args
        undefined = [arg for arg in original_args_list if arg not in kwargs]
        if undefined:
            raise Exception("We don't know what to do with "+str(undefined))
        star_args = [kwargs[arg] for arg in original_args_list]
        return function(*star_args)
    return inner



if __name__ == "__main__":
    @inject
    def foo(bar, baz): return bar + baz

    assert foo(some_undefined=5, baz="baz", bar="bar") == "barbaz"