# functions go here

def yes_no(question):

   """checks user response to a question is yes / no (y/n), 'yes' or 'no' """

    while True:

        response = input(question).lower()

        # chech the user says yes / no / y / n
        if response == "yes" or response == "y":
            return "yes"
        elif response == "no" or response == "n":
            return "no"
        else:
            print("please enter yes / no")

#Main routine

want_instructions = yes_no("Do you want to see the instructions? ").lower()

print("we done")