# functions go here

# usage
def yes_no(question):

    while True:
        response = input(question).lower()

        # check 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")


def instructions():
   """ Prints instructions """
   print("""
   *** Instructions ****
   Roll the dice and try to win!
   """)

# Main routine
while True:
    want_instructions = yes_no("Do you want to see the instructions? ")
    if want_instructions == "yes":
        instructions()

    print ("Program continues")