if value is None:
self.experimentSerial = None
self.dataSourceSerial = None
elif self.topObject.nmrProject is value.topObject:
self.experimentSerial = value.experiment.serial
self.dataSourceSerial = value.serial
else:
raise ApiError("%s does not belong to NmrCalcStore.nmrProject %s" % (value,self.topObject.nmrProject ))