我想在单击TextField时在InputView中显示DatePicker

Question

每当我尝试此代码时，它都会显示错误

from random import choice

questions = ["Why is the sky blue?: ", "Why is there a face on the moon?: ",
             "Where are all the dinosaurs: "]

question = choice(questions)
answer = input(question).strip().lower()

while answer != "just because":
    answer = input("why?: ").strip().lower()

print("Oh... Okay")

我尝试了很多解决方案，观看了许多成功的视频，但是当我尝试使用自己的代码时，它会显示上述错误

Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value (lldb)