def test_remove(self):
        prio_set_list = event._PrioritizedSetList()
        obj = (1,)

        prio_set_list.add(1, obj)
        assert prio_set_list
        prio_set_list.remove(obj)
        assert not prio_set_list

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.remove(obj)
        excinfo.match(r"can not be found")
def get_level(self, level, queue):
		if queue == None:
			queue = []
		if level == 1:
			queue.push(self)
		else:
			if self.lchild != None:
				self.lchild.get_level(level-1, queue)
			if self.rchild != None:
				self.rchild.get_level(level-1, queue)
		return queue