def METHOD_NAME(self):
    """
    Which LPG machine vertex is targeted by which machine vertex
    and partition.
    :return:
         A set of (LPG machine vertex, source machine vertex, partition_id)
    :rtype: set(tuple(LivePacketGatherMachineVertex,
        ~pacman.model.graphs.machine.MachineVertex, str))
    """
    return self.__targeted_lpgs