只有在输入 "yes" 时，我的 while 循环才能确保给出有效答案

Question

userans = input("Do you want to become a member of Friends of Seaview Pier? ").lower()
while not (userans == "yes" and "no"):
  userans = input("Do you want to become a member of Friends of Seaview Pier? ").lower()
  print (userans)
if userans == "yes":
  Appdata = Application()
  userans2 = input("Do you want to volunteer at Seaview Pier? ").lower()
  if userans2 == "yes":
    Vdata = Volunteerdata()
    CombinedData = [Appdata, Vdata]
    Data.append(CombinedData)
    print(Data)
  else:
    print("Thank you for considering.")
    Vdata = (["no"])
    CombinedData = [Appdata, Vdata]
    Data.append(CombinedData)
    print(Data)
elif userans == "no":
  print("Thank you for your consideration.")

那里有一些打印功能，所以我可以检查它在运行时输入和输出的内容。为了方便起见，我也没有包含我创建的函数，因为我很确定这是这里这段代码的问题，而不是它们。
输出和输入的示例如下：

Do you want to become a member of Friends of Seaview Pier? no
Do you want to become a member of Friends of Seaview Pier? no
no
Do you want to become a member of Friends of Seaview Pier? on
on
Do you want to become a member of Friends of Seaview Pier? no
no
Do you want to become a member of Friends of Seaview Pier? yes
yes
Enter your first name:

Answer 1

while not (userans == "yes" and "no")

这是检查多个值的错误方法。

改用这个：

while userans != "yes" and userans != "no":

甚至更好：

while userans not in ["yes", "no"]:

只有在输入 "yes" 时，我的 while 循环才能确保给出有效答案

My while loop to make sure a valid answer is being given only goes through when "yes" is inputted

python

while-loop