python学习，day1作业：设计一个三级菜单

设计一个三级菜单，要求能够下钻，能够推出，比较笨的方法

 # coding=utf-8
 # Author: RyAn Bi
 data = {
     'beijing':{
         'changping':{
             'wudaokou':['oldboy','test'],
             'sanlitun':['oldboy','test'],
             'wangjing':['oldboy','test']
         },
         'dongcheng':{
             'wudaokou':['oldboy','test'],
             'sanlitun':['oldboy','test'],
             'wangjing':['oldboy','test']
         },
         'xicheng':{
             'wudaokou':['oldboy','test'],
             'sanlitun':['oldboy','test'],
             'wangjing':['oldboy','test']
         }
     },
     'henan':{
         'zhengzhou':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         },
         'xuchang':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         },
         'lohe':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         }
     },
     'shandoong':{
         'jinan':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         },
         'qingdao':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         },
         'weihai':{
             'wudaokou':[],
             'sanlitun':[],
             'wangjing':[]
         }
     }
 }

 #print( data)
 exit_flag = False

 while not exit_flag:
     for i in data:
         print(i)
     chose1 = input('where is your home:')
     if chose1 in data:
         while not exit_flag:
             for i2 in data[chose1]:
                 print(i2)
             chose2 = input('where is your home:')
             if chose2 in data[chose1]:
                 while not exit_flag:
                     for i3 in data[chose1][chose2]:
                         print(i3)
                     chose3 = input('where is your home:')
                     if chose3 in data[chose1][chose2]:
                         while not exit_flag:
                             for i4 in data[chose1][chose2][chose3]:
                                 print(i4)
                             chose4 = input('push q come back')
                             if chose4 == 'b':
                                 break
                             elif chose4 =='q':
                                 exit_flag = True
                     if chose3 == 'b':
                         break
                     elif chose3 =='q':
                         exit_flag = True
             if chose2 == 'b':
                 break
             elif chose2 =='q':
                 exit_flag = True