class_docstr: GOMS HRIT format reader.
code: def _getitem(block, lut):
      return lut[block]
  
imports: import logging
  from datetime import datetime
  import numpy
  import xarray
  from satpy.readers._geos_area import get_area_definition, get_area_extent
  from satpy.readers.hrit_base import HRITFileHandler, ancillary_text, annotation_header, base_hdr_map, image_data_function, time_cds_short
label_desc: Use image node_id 4 for calling the HRITGOMSFileHandler obj's underlying member method code with example usage: obj._getitem(block, lut) and returns: lut