利用字典实现多级菜单效果

list = {"Bei Jing":("chaoyang","haidian"),"ShangHai":("putuo","XXXX"),"AnHui":{"HeFei":("yaohai","shushan","zhengwu","binhu")}}
chose = " "
chose2 = " "
chose3 = " "
flag = 0
while True:
print("一级菜单:",[i for i in list])
if chose !="":
chose = input("please input u chose!")
while True:
if chose in list:
print("二级菜单:", [v for v in list[chose]])
chose2 = input("please input u chose!")
if chose2 in list[chose]:
try:
print("三级菜单:", [v for v in list[chose][chose2]])
except:
continue
                    if chose3 !="":
while True:
chose3 = input("please input u chose!")
if chose3 == "last":
chose3 = ""
break
                            elif chose3 in list[chose][chose2]:
print("没有下级菜单")
elif chose3 =="quit":
chose2 = "quit"
break
                            else:
print("非法输入！")
if chose2 == "quit":
break
                elif chose2 == "last":
chose2 = ""
break
                elif chose2 in list[chose]:
chose3 = " "
else:
print("非法输入！")
if(chose =="quit"):
break
        if chose == "quit" or chose2 == "quit" or chose3 == "quit":
break
    else:
if chose == "quit":
break
        elif chose == "last":
print("没有上级菜单")
elif chose in list:
chose2 = " "
else:
print("非法输入！")