def __init__(self, name, host='127.0.0.1', port=27017):
        self.name = name
        self.host = host
        self.port = port
def draw_paths(c, tree):
	if tree.lchild == None or tree.rchild == None:
		return
	tree.lchild.leaf.draw_path(c, tree.rchild.leaf)
	draw_paths(c, tree.lchild)
	draw_paths(c, tree.rchild)