class_docstr: Test VISSR file handler.
class_docstr_tok: ["Test","VISSR","file","handler","."]
docstr: Get IR1 calibration block.
docstr_tok: ["Get","IR1","calibration","block","."]
code: def ir1_calibration(self):
      """Get IR1 calibration block."""
      cal = np.zeros(1, dtype=fmt.IR_CALIBRATION)
      table = cal[
          "conversion_table_of_equivalent_black_body_temperature"
      ]
      table[0, 0:4] = np.array([0, 100, 200, 300])
      return cal
  
imports: import datetime
  import gzip
  import fsspec
  import numpy
  import pytest
  import xarray
  from pyresample.geometry import AreaDefinition
  import satpy.tests.reader_tests.gms.test_gms5_vissr_data
  from satpy.readers import FSFile
  from satpy.tests.reader_tests.utils import get_jit_methods, skip_numba_unstable_if_missing
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 20 for calling the TestFileHandler obj's underlying member method code with example usage: obj.ir1_calibration() and returns: cal