code: def read_geo(fid, key):
      
      dsid = GEO_NAMES[key.name]
      add_epoch = False
      if "time" in key.name:
          days = fid["/L1C/" + dsid["day"]].value
          msecs = fid["/L1C/" + dsid["msec"]].value
          data = _form_datetimes(days, msecs)
          add_epoch = True
          dtype = np.float64
      else:
          data = fid["/L1C/" + dsid].value
          dtype = np.float32
      data = xr.DataArray(da.from_array(data, chunks=CHUNK_SIZE),
                          name=key.name, dims=['y', 'x']).astype(dtype)
  
      if add_epoch:
          data.attrs['sensing_time_epoch'] = EPOCH
  
      return data
docs: Read geolocation and related datasets.