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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 _apply_filter(self, filters, candidates):
 """ Apply vector filters if specified and return filtered list """

        if filters:
            filter_input = candidates
            for fetch_vector_filter in filters:
                filter_input = fetch_vector_filter.filter_vectors(filter_input)

            return filter_input
        else:
            return candidates