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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 _calculate_num_queries(self):
 """ Calculate the total number of request and response queries. Used for count header and count table. """

        request_totals = self._totals("request")
        response_totals = self._totals("response")

        return request_totals[2] + response_totals[2]