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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 _get_response_ms(self):
 """ Get the duration of the request response cycle is milliseconds. In case of negative duration 0 is returned. """

        response_timedelta = now() - self.log['requested_at']
        response_ms = int(response_timedelta.total_seconds() * 1000)
        return max(response_ms, 0)