在Python中使用not关键字时遇到For循环问题

Question

我在这方面做了很多研究，但我不知道我做错了什么。请帮忙！！！你知道吗

课程目标： 不断地问一个问题来为用户选择一个选项，直到用户在提供的列表中选择一个为止。 问题：我就是无法使用not关键字。你知道吗

代码语法：

items = {'1': '2', '3': '4', '5': '6'}
choice = input("Select your item: ")
print(choice)
for choice not in items:
    if choice in items:
        the_choice = items[choice]
        print("You chose",the_choice)
        break
    else:
        print("Uh oh, I don't know about that item")

来自eclipse的错误：

for not choice in items:
          ^
SyntaxError: invalid syntax

Answer 1

items = {'1': '2', '3': '4', '5': '6'}
choice = ''

while choice not in items:
    choice = input("Select your item: ")
    print(choice)
    if choice in items:
        the_choice = items[choice]
        print("You chose",the_choice)
    else:
        print("Uh oh, I don't know about that item")

Answer 2

只需忽略代码中的not关键字

items = {'1': '2', '3': '4', '5': '6'}
    choice = input("Select your item: ")
    print(choice)
    for choice  in items:
       if choice in items:
        the_choice = items[choice]
        print("You chose",the_choice)
        break
    else:
        print("Uh oh, I don't know about that item")

Answer 3

试试这个：

items = {'1': '2', '3': '4', '5': '6'}

while True:
    choice = input("Select your item: ")
    print(choice)
    if choice in items:
        the_choice = items[choice]
        print("You chose",the_choice)
        break

    print("Uh oh, I don't know about that item")