code: def output(self):
          
          subts = [rms.output for rms in self._subsims]
          distaxis = subts[0].ndim - 1
          return DistTimeseries(subts, distaxis, self._node_labels())
docs: Rank 3 array representing output time series. Axis 0 is time, 
          axis 1 ranges across output variables of a single simulation, axis 2 
          ranges across different simulation instances.