class_docstr: Unit tests for SEVIRI calibration handler.
class_docstr_tok: ["Unit","tests","for","SEVIRI","calibration","handler","."]
docstr: Test exceptions raised by the calibration handler.
docstr_tok: ["Test","exceptions","raised","by","the","calibration","handler","."]
code: def test_calibrate_exceptions(self):
      """Test exceptions raised by the calibration handler."""
      calib = self._get_calibration_handler()
      with pytest.raises(
          ValueError,
          match="Invalid calibration invalid for channel IR_108",
      ):
          calib.calibrate(None, "invalid")
  
imports: import unittest
  from datetime import datetime
  import numpy
  import pytest
  import xarray
  from satpy.readers.seviri_base import SEVIRICalibrationAlgorithm, SEVIRICalibrationHandler
label_desc: Use image node_id 3 for calling the TestSeviriCalibrationHandler obj's underlying member method code with example usage: obj.test_calibrate_exceptions() without return types