code: def test_filehandler_returns_area(insat_filehandler):
      """Test that filehandle returns an area."""
      fh = insat_filehandler
  
      ds_id = make_dataid(
          name="MIR",
          resolution=4000,
          calibration="brightness_temperature",
      )
      area_def = fh.get_area_def(ds_id)
      _ = area_def.get_lonlats(chunks=1000)
      assert (
          subsatellite_longitude
          == area_def.crs.to_cf()["longitude_of_projection_origin"]
      )
  
imports: import os
  from datetime import datetime
  import dask.array
  import h5netcdf
  import numpy
  import pytest
  from satpy import Scene
  from satpy.readers.insat3d_img_l1b_h5 import CHANNELS_BY_RESOLUTION, LUT_SUFFIXES, Insat3DIMGL1BH5FileHandler, get_lonlat_suffix, open_dataset, open_datatree
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 18 for calling a global function with example usage: test_filehandler_returns_area(insat_filehandler) without return types