#coding:utf-8__author__ = 'similarface'class KeyedBinaryTree:    def __init__(self):self.tree=EmptyNode()    def __repr__(self):return repr(self.tree)    def lookup(self,key):return self.tree.lookup(key)    def insert(self,key,val):self.tree=self.tree.insert(key,val)class EmptyNode:    def __repr__(self):        return '*'    def lookup(self,key):        return None    def insert(self,key,val):        return BinaryNode(self,key,val,self)class BinaryNode:    def __init__(self,left,key,val,right):        self.key,self.val=key,val        self.left,self.right=left,right    def lookup(self,key):        if self.key==key:            return self.val        elif self.key>key:            return self.left.lookup(key)        else:            return self.right.lookup(key)    def insert(self,key,val):        if self.key==key:            self.val=val        elif self.key>key:            self.left=self.left.insert(key,val)        elif self.key