装饰器中的“未绑定的本地错误”

Question

我收到的错误令我非常难过。

#! /usr/bin/env python3
from sys       import modules
from inspect   import isclass
from functools import partial
from abc       import abstractmethod
from abc       import ABC as AbstractClass


class Decoration(AbstractClass):
    defaults = {}

    def __init__(self, *list, **map):
        self.list = list
        self.map = map

    def __get__(self, caller, owner):
        return partial(self.__call__, caller)

    @abstractmethod
    def __call__(self, decoratee, *list, **map):
        pass

    @staticmethod
    def set_defaults(defaults):
        Decoration.defaults = defaults


class Decorator(Decoration):

    def __init__(self, *list, **map):
        super().__init__(self, *list, **map)

    def __call__(self, function, *list, **map):
        print(function)
        def decorated(*list, **map):
            if map:
                for decorator in map:
                    for arguments in map[decorator]:
                        function = getattr([__name__], decorator)(function, arguments)
            return function(*list, **map)
        return decorated


@Decorator()
def dummy(*list, **map):
    for item in list:
        print(item)
    for k, v in map:
        print('{} {}'.format(k, v))


def main():
    dummy({'banana': True})


if __name__ == '__main__':
    main()

在“function = getattr ...”行中，我收到此错误：

UnboundLocalError: local variable 'function' referenced before assignment

我很困惑主要是因为上面的print语句将函数的定义发现为

<function dummy at (address)>

这是正确的。此外，删除该行可使程序正常运行并返回当前下一行。据我所知，这不是getattr的语法问题。有什么想法吗？