def test_add_already_added(self):
        prio_set_list = event._PrioritizedSetList()
        obj = object()
        prio_set_list.add(0, obj)

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(0, obj)
        excinfo.match(r"has already been added")

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(1, obj)
        excinfo.match(r"has already been added")
def split_container(container, iter):
	root = Tree(container)
	if iter != 0:
		sr = random_split(container)
		if sr!=None:
			root.lchild = split_container(sr[0], iter-1)
			root.rchild = split_container(sr[1], iter-1)
	return root