class_docstr: Test the FY3E MERSI-LL L1B reader.
docstr: Test loading data at radiance calibration.
docstr_tok: ["Test","loading","data","at","radiance","calibration","."]
code: def test_rad_calib(self):
      """Test loading data at radiance calibration."""
      from satpy.readers import load_reader
      from satpy.tests.utils import make_dataid
  
      filenames = self.filenames_all
      reader = load_reader(self.reader_configs)
      files = reader.select_files_from_pathnames(filenames)
      assert 4 == len(files)
      reader.create_filehandlers(files)
      # Make sure we have some files
      assert reader.file_handlers
  
      ds_ids = []
      for band_name in ["1", "3", "4", "6", "7"]:
          ds_ids.append(
              make_dataid(name=band_name, calibration="radiance")
          )
      res = reader.load(ds_ids)
      assert len(res) == 5
      assert res["1"].shape == (2 * 10, 2048)
      assert res["1"].attrs["calibration"] == "radiance"
      assert res["1"].attrs["units"] == "mW/ (m2 cm-1 sr)"
      assert res["3"].shape == (2 * 10, 2048)
      assert res["3"].attrs["calibration"] == "radiance"
      assert res["3"].attrs["units"] == "mW/ (m2 cm-1 sr)"
      assert res["4"].shape == (2 * 10, 2048)
      assert res["4"].attrs["calibration"] == "radiance"
      assert res["4"].attrs["units"] == "mW/ (m2 cm-1 sr)"
      assert res["6"].shape == (2 * 40, 2048 * 2)
      assert res["6"].attrs["calibration"] == "radiance"
      assert res["6"].attrs["units"] == "mW/ (m2 cm-1 sr)"
      assert res["7"].shape == (2 * 40, 2048 * 2)
      assert res["7"].attrs["calibration"] == "radiance"
      assert res["7"].attrs["units"] == "mW/ (m2 cm-1 sr)"
  
imports: import os
  from unittest import mock
  import dask.array
  import numpy
  import pytest
  import xarray
  from satpy.tests.reader_tests.test_hdf5_utils import FakeHDF5FileHandler
label_desc: Use image node_id 2 for calling the TestMERSILLL1B obj's underlying member method code with example usage: obj.test_rad_calib() without return types