code: def calibrate(self, data, calibration):
          
          tic = datetime.now()
          if calibration == 'counts':
              res = data
          elif calibration in ['radiance', 'brightness_temperature']:
              res = self._calibrate(data)
          else:
              raise NotImplementedError("Don't know how to calibrate to " +
                                        str(calibration))
  
          res.attrs['standard_name'] = calibration
          res.attrs['calibration'] = calibration
  
          logger.debug("Calibration time " + str(datetime.now() - tic))
          return res
docs: Calibrate the data.