def METHOD_NAME(self):
    file = ModelicaMOS(self.data_dir / 'B2_no_water_load.mos')
    self.assertEqual(file.retrieve_header_variable_value('Peak water heating load', cast_type=float), 0)
    file.replace_header_variable_value('Peak water heating load', 5124)
    file.replace_header_variable_value('Peak space cooling load', -10000)
    # save off the new file
    file.save_as(self.output_dir / 'B2_no_water_load_updated.mos')
    # reread the saved file and check the values
    new_file = ModelicaMOS(self.output_dir / 'B2_no_water_load_updated.mos')
    self.assertEqual(new_file.retrieve_header_variable_value('Peak water heating load', cast_type=float), 5124)
    self.assertEqual(new_file.retrieve_header_variable_value('Peak space cooling load', cast_type=float), -10000)
    # just call the save method for 'crash' check
    new_file.save(