code: def query_metric(self, metric_type, metric_id, start=None, end=None, **query_options):
          
          if start is not None:
              if type(start) is datetime:
                  query_options['start'] = datetime_to_time_millis(start)
              else:
                  query_options['start'] = start
  
          if end is not None:
              if type(end) is datetime:
                  query_options['end'] = datetime_to_time_millis(end)
              else:
                  query_options['end'] = end
  
          return self._get(
              self._get_metrics_raw_url(
                  self._get_metrics_single_url(metric_type, metric_id)),
              **query_options)
docs: Query for metrics datapoints from the server.
  
          :param metric_type: MetricType to be matched (required)
          :param metric_id: Exact string matching metric id
          :param start: Milliseconds since epoch or datetime instance
          :param end: Milliseconds since epoch or datetime instance
          :param query_options: For possible query_options, see the Hawkular-Metrics documentation.