# Check that users have entered a valid
# option based on a list
def string_checker(user_response, valid_ans):
    while True:

        #get user responce and make sure its lowercase
        user_response = input(question).lower()

        for item in valid_ans:
            # check if the user responce is a word in the list
            if item == user_response:
                return item

            # check if the user responce is the same as
            # the first letter of an item in the list\
            elif user_response == item[0] :
                return item


# Main routine goes here

yes_no = ["yes", "no"]
rps_list = ["rock", "paper", "scissors","xxx"]

want_instructions = string_checker("Do you want to see the instructions",
                                   yes_no)

print("you chose", want_instructions)