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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 delay_response_series(self):
 """A tuple of two numpy arrays, which hold the time delays and the associated iuh values respectively."""

        delays = []
        responses = []
        sum_responses = 0.
        for t in itertools.count(self.dt_response/2., self.dt_response):
            delays.append(t)
            response = self(t)
            responses.append(response)
            sum_responses += self.dt_response*response
            if (sum_responses > .9) and (response < self.smallest_response):
                break
        return numpy.array(delays), numpy.array(responses)