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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def filter(filter_creator):
 """ Creates a decorator that can be used as a filter. .. warning:: This is currently not compatible with most other decorators, if you are using a decorator that isn't part of `hurler` you should take caution. """

    filter_func = [None]

    def function_getter(function):
        if isinstance(function, Filter):
            function.add_filter(filter)

            return function
        else:
            return Filter(
                filter=filter_func[0],
                callback=function,
            )

    def filter_decorator(*args, **kwargs):
        filter_function = filter_creator(*args, **kwargs)

        filter_func[0] = filter_function

        return function_getter

    return filter_decorator