python3 三级菜单-基础版

data = {
"北京":{
"东城区":{
"安定门":["国子监","孔庙","钟楼"],
"建国门":["金宝街","长安街","西街"],
"朝阳门":["东四","新街口","孚王府"],
},
"朝阳区":{
"和平街":["顾家庄","樱花社区","东街"],
"八里屯":["慈寿寺","定慧寺","前门"],
"三里屯":["夜店","工体","后海酒吧"],
},
"海淀":{
"中关村":["海龙","鼎好","科贸"],
"五道口":["清华","北大","人大"],
"航天桥":["公主坟","古城","长安街"],
},
}
}

exit_flag =False

while not exit_flag:
for i in data:
print(i)

choice = input("选择1")
if choice in data:
    while not exit_flag:
        for i2 in  data[choice]:
            print("\t",i2)
        choice2 = input("选择2")
        if choice2 in data[choice]:
            while not exit_flag:
                for i3 in data[choice][choice2]:
                    print("\t\t",i3)
                choice3 = input("选择3")
                if choice3 in data[choice][choice2]:
                    for i4 in data[choice][choice2][choice3]:
                        print("\t\t\t",i4)
                    choice4 = input("最后一层，按b返回")
                    if choice4 == "b":
                        pass
                    elif choice4 == "q":
                        exit_flag = True
                if choice3 == "b":
                    break
                elif choice3 == "q":
                    exit_flag = True
        if choice2 == "b":
            break
        elif choice2 == "q":
            exit_flag = True