# Check that users have entered a valid
# option based on a list
def string_checker(question, valid_ans=("yes", "no")):

    error = f'please enter a valid option from the following list: {valid_ans}'

    while True:

        #get user response and turn it lowercase
        user_response = input(question).lower()

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

            #check if the user response is the same as the first letter of an item in the list

            elif user_response == item[0]:
                return item

        #print error if user not enter correct
        print(error)
        print()

#displays instructions

def instructions():
    print('''
    paper beat rock, rock best scissors, scissors beat paper.
    
    gl
    
    
    ''')



#main routine goes here


rps_list = ["rock", "paper", "scissors", "xxx"]

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

print("you chose: ", want_instructions)
# checks users enter y or n
if want_instructions == 'yes':
    instructions()

user_choice =string_checker("chose: ", rps_list)
print("You chose: ", user_choice)