code: def distance(self) -> ErrorValue:
          
          if 'DistCalibrated' in self._data:
              dist = self._data['DistCalibrated']
          else:
              dist = self._data["Dist"]
          if 'DistCalibratedError' in self._data:
              disterr = self._data['DistCalibratedError']
          elif 'DistError' in self._data:
              disterr = self._data['DistError']
          else:
              disterr = 0.0
          return ErrorValue(dist, disterr)
docs: Sample-to-detector distance