三級菜單

The following code is 3 level menu, which is based on the list. But there is still some errors I can't fix them: we can't go back main menu by pressing "b", even this command doesn't exist, I don't know if it is PyCharm's problem. I wii try to fix them later.

 

#多級字典及嵌套操做city_province = {    "SiChuan" : {        "ChengDu": {                    "JingJiangQu": ["銀石廣場", "春熙路"],                    "WuHouQu": ["武侯祠"]                    },        "MianYang":["345"],        "DeYang":["678"],        "LuZhou":["789"],        "PanZhiHua":["91011"],        "LeShan":["101112"],        "GuangAn":["111213"]    },    "GuiZhou": {        "GuiYang": ["123"],        "ZunYiShi": ["234"],        "AnShunShi": ["345"],        "FuQuanShi": ["456"],        "KaiLiShi": ["567"],        "XingYiShi": ["678"]    },    "YunNan": {        "KunMing": ["123"],        "QuJing": ["234"],        "YuXi": ["345"],        "BaoShan": ["456"],        "LiJiang": ["567"],        "PuEr": ["678"],        "XuanWei": ["789"]    }}# print(city_province["YunNan"]["KunMing"][0])# print(city_province.values())# print(city_province.keys())while True:    for index, i in enumerate(city_province):        print(index, i)    choice = input("input your province: ")    if choice in city_province:        while True:            for i2 in city_province[choice]:                print("\t", i2)            choice_2 = input("input your city:")            if choice_2 in city_province[choice]:                while True:                    for i3 in city_province[choice][choice_2]:                        print("\t\t", i3)                    choice_3 = input("input your choice to get more details: ")                    if choice_3 in city_province[choice]:                        for i4 in city_province[choice][choice_2][choice_3]:                            print("\t\t", i4)                        choice_4 = input("press b to go back the main menu: ")                        if choice_4 == "b":                           pass                if choice_3 == "b":                    break        if choice_2 == "b":            break