My first program and first blogs-三级菜单

_author Administrator
#date 2018/9/7
items = {
            '陕西':{
                '西安':['周至','户县','蓝田' ],
                '宝鸡':['蔡家坡','陈仓','凤县']
                    },
          '山东':{
                '烟台':['栖霞','枣庄','c'],
                '青岛':['a','b','d']
                   }
         }
print(items)
a = '陕西'
b = '山东'
a1 = '宝鸡'
a2 = '西安'
flag = True
while flag:
    choice1 = input('please input you decide1 [陕西/山东]:')
    if choice1 == a:
        print(items[a])
        while flag:
            choice2 = input('please input you decide2 [西安/宝鸡]:')
            if choice2 == a1:
                print(items[a][a1])
                while flag:
                    choice3 = int(input('please input you number:'))
                    if choice3 < 3:
                        print(items[a][a1][choice3-1])
                        flag = False
                    else:
                        flag = True
            elif choice2 == a2:
                print(items[a][a2])
                while flag:
                    choice3 = int(input('please input you number:'))
                    if choice3 < 3:
                        print(items[a][a2][choice3-1])
                        flag = False
            else:
                flag = True
    else:
        flag = True