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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 _responses(self, request):
 """ internal API, returns an iterator with all responses matching the request. """

        request = self._before_record_request(request)
        for index, (stored_request, response) in enumerate(self.data):
            if requests_match(request, stored_request, self._match_on):
                yield index, response