# function go here

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

    while True:

        response = input(question).lower()

        # check the user says yes / no
        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

# ask the user if they want instructions (check they say yes / no)
want_instructions = yes_no("Do you want the see the instructions? ")

# Display the instructions if the user wants to see them...
if want_instructions == "yes":
    instructions()

print()
print("Program continues")