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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 add_filter(self, files_filter, filter_type=DefaultFilterType):
 """ Add a files filter to this iterator. For a file to be processed, it must match ALL filters, eg they are added with ADD, not OR. :param files_filter: filter to apply, must be an object inheriting from filters.FilterAPI. :param filter_type: filter behavior, see FilterType for details. """

        self.__filters.append((files_filter, filter_type))
        return self