code: def _read_channel(channel, stream, start, duration):
      
      channel_type = lalframe.FrStreamGetTimeSeriesType(channel, stream)
      read_func = _fr_type_map[channel_type][0]
      d_type = _fr_type_map[channel_type][1]
      data = read_func(stream, channel, start, duration, 0)
      return TimeSeries(data.data.data, delta_t=data.deltaT, epoch=start,
                        dtype=d_type)
docs: Get channel using lalframe