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