三级菜单

# 不完美
data = {
    '北京':{
        '海淀':{
            '五道口':{
                'soho':{},
                '网易':{},
                'google':{}
            },
            '中关村':{
                '爱奇艺':{},
                '汽车之家':{},
                'youku':{},
            },
            '上地':{
                '百度':{},
            },
        },
        '昌平':{
            '沙河':{
                '老男孩':{},
                '北航':{},
            },
            '天通苑':{},
            '回龙观':{},
        },
        '朝阳':{},
        '东城':{},
    },
    '上海':{
        '闵行':{
            "人民广场":{
                '炸鸡店':{}
            }
        },
        '闸北':{
            '火车战':{
                '携程':{}
            }
        },
        '浦东':{},
    },
    '山东':{},
}
Flag = True
for i in data:
    print(i)
while Flag:
    Choose_01 = input("Choose>>>")
    if Choose_01 in data:
        for i in data[Choose_01]:
            print(i)
        while Flag:
            Choose_02 = input("Choose>>>")
            if Choose_02 in data[Choose_01]:
                for i in data[Choose_01][Choose_02]:
                    print(i)
                while Flag:
                    Choose_03 = input("Choose>>>")
                    if Choose_03 in data[Choose_01][Choose_02]:
                        for i in data[Choose_01][Choose_02][Choose_03]:
                            print(i)
                        exit("No more Choice, now exit.")
                    elif Choose_03 == 'q':
                        print("Go Back")
                        for i in data[Choose_01]:
                            print(i)
                        break
                    else:
                        print("Not Exsit_layer 3, choose again.")
                        for i in data[Choose_01][Choose_02]:
                            print(i)
            elif Choose_02 == 'q':
                print("Go Back")
                for i in data:
                    print(i)
                break
            else:
                print("Not Exsit_layer 2, choose again.")
                for i in data[Choose_01]:
                    print(i)
    elif Choose_01 == 'q':
        print("Exit")
        break
    else:
        print("Not Exsit_layer 1, choose again.")
        for i in data:
            print(i)