Sets internal file filters to `file_filters` by tossing old state.
        `file_filters` can be single object or iterable.

def set_file_filters(self, file_filters):
        """
        Sets internal file filters to `file_filters` by tossing old state.
        `file_filters` can be single object or iterable.
        """
        file_filters = util.return_list(file_filters)
        self.file_filters = file_filters