code: def delete_value(self, label=None):
          
          evt = self._client._request_point_value_delete(self.__lid, self.__pid, self._type, label=label)
          self._client._wait_and_except_if_failed(evt)
docs: Delete the labelled value (or all values) on this Point
  
          Raises [IOTException](./Exceptions.m.html#IoticAgent.IOT.Exceptions.IOTException)
          containing the error if the infrastructure detects a problem
  
          Raises [LinkException](../Core/AmqpLink.m.html#IoticAgent.Core.AmqpLink.LinkException)
          if there is a communications problem between you and the infrastructure
  
          `label` (optional) (string) the label for the value you want to delete. If not specified, all values for this
          point will be removed.