Sage program question

[sparkz_alot]

First some house cleaning.
You don't need line 4. Lines 6 & 7 can be written as

questionmark = "?"
haddaway = "What is love?"

How can I let python check for the intended input in a practical manner?

Usually you can do this with the "try/except" statement, for example:

answer = ["yes", "no"]

while True:
    try:
        response = input("Enter your response: ")
        if response in answer:
            print("Correct response")
            break
        else:
            print("Wrong response, try again")
            continue
    except ValueError as err:
        print("There was an error {}".format(err))

print("Done")