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 / y / n
        if response == "yes" or response == "y":
            return "yes"
        elif response == "no" or response == "n":
            return "no"
        else:
            print("please enter yes / no")

# Displays instructions
def instructions():
    print('''
    
*** Instructions ****

To begin, choose the number of rounds (or press <enter> for infinite mode).

Then play against the computer. You need to choose R (rock),
P (paper) or S (scissors).

The rules are as follows:
Paper beats rock
Rock beats scissors
Scissors beats paper

Press <xxx> to end the game at anytime.

Good Luck!
    ''')


#Main routine
print()
print("💎📰✂ Rock / Paper / Scissors Game ✂💎📰")
print()

# ask the user if they want to see the instructions and display
#them if requested
want_instructions = yes_no("Do you want to read the instructions? ")

#checks users enter yes (y) or no (n)
if want_instructions == "yes":
    instructions()

print("Program continues")