这个avl树为什么只插入了一个节点？

Question

问题遇到的现象和发生背景

调试的时候所有语句都执行了，但是插入完成之后发现只有第一个节点在树中

问题相关代码，请勿粘贴截图

class Node:
    def __init__(self,key):
        self.key = key
        self.lc = None
        self.rc = None
        self.height = 0

class AVLTree:
    '''avl操作'''
    def __init__(self):
        self.node = None
    def GetHeight(self,node):
        if node:
            return node.height
        else:
            return -1
    def LeftRotation(self,A):
        B = A.lc
        A.lc = B.rc
        B.rc = A
        B.height = max(self.GetHeight(B.lc),self.GetHeight(A)) + 1
        A.height = max(self.GetHeight(A.rc),self.GetHeight(A.lc)) + 1
    def RightRotation(self,A):
        B = A.rc
        A.rc = B.lc
        B.lc = A
        B.height = max(self.GetHeight(B.rc),self.GetHeight(A)) + 1
        A.height = max(self.GetHeight(A.rc),self.GetHeight(A.lc)) + 1
        return A
    def LaRRotation(self,A):
        A.lc = self.RightRotation(A.lc)
        return self.LeftRotation(A)
    def RaLRotation(self,A):
        A.rc = self.LeftRotation(A.rc)
        return self.RightRotation(A)
    '''树操作'''
    def put(self,key):
        if self.node == None:
            self.node = Node(key)
        else:
            self.node = self._put(key,self.node)
    def _put(self,key,anode):
        if anode == None:
            anode = Node(key)
        elif key < anode.key:
            anode.lc = self._put(key,anode.lc)
            if (self.GetHeight(anode.lc) - self.GetHeight(anode.rc)) == 2:
                if key < anode.lc.key:
                    node = self.LeftRotation(anode)
                else:
                    node = self.RaLRotation(anode)
        elif key > anode.key:
            anode.rc = self._put(key,anode.rc)
            if (self.GetHeight(anode.rc) - self.GetHeight(anode.lc)) == 2:
                if key > anode.rc.key:
                    anode = self.RightRotation(anode)
                else:
                    anode = self.LaRRotation(anode)
        else:
            pass
        anode.height = max(self.GetHeight(anode.lc),self.GetHeight(anode.rc)) + 1
        return anode
    def PreOrder(self,node):
        if (node == None):
            return
        else:
            self.PreOrder(node.lc)
            print(node.key,end=' ')
            self.PreOrder(node.rc)

def max(a,b):
    return a if a > b else b

if __name__ == '__main__':
    tree = AVLTree()
    tree.put(1)
    tree.put(2)
    tree.put(3)
    tree.put(4)
    tree.put(5)
    tree.PreOrder(tree.node)
    
        

运行结果及报错内容

Answer 1

红框部分代码有问题， 注释掉了，就可以看到5个元素