code: def select_interval(self, end_time, start_time=None):
          
          new_query = copy.deepcopy(self)
          new_query._end_time = end_time
          new_query._start_time = start_time
          return new_query
docs: Copy the query and set the query time interval.
  
          Example::
  
              import datetime
  
              now = datetime.datetime.utcnow()
              query = query.select_interval(
                  end_time=now,
                  start_time=now - datetime.timedelta(minutes=5))
  
          As a convenience, you can alternatively specify the end time and
          an interval duration when you create the query initially.
  
          :type end_time: :class:`datetime.datetime`
          :param end_time: The end time (inclusive) of the time interval
              for which results should be returned, as a datetime object.
  
          :type start_time: :class:`datetime.datetime`
          :param start_time:
              (Optional) The start time (exclusive) of the time interval
              for which results should be returned, as a datetime object.
              If not specified, the interval is a point in time.
  
          :rtype: :class:`Query`
          :returns: The new query object.