The post Placement Code can establish master-slave relationship:
def abc():
nbAgent = cmds.getAttr("McdPlace0.numOfAgent")
for i in range(nbAgent):
agent1 = "McdAgent" + str(i + 1)
agent2 = "McdAgent" + str(i + nbAgent + 1)
agent3 = "McdAgent" + str(i + nbAgent + 11)
cmds.connectAttr(agent1 + ".masterOf", agent2 + ".masterOf")
cmds.connectAttr(agent1 + ".masterOf", agent3 + ".masterOf")
...