# Functions go here
def string_check(question, valid_ans_list):
    """Checks that users enter the full word
    or the first letter of a word from  list of valid responses"""

    while True:

        response = input(question).lower()

        for item in valid_ans_list:
            if response == item:
                return item

            # check if it's the first letter
            elif response == item[0]:
                return item

        print(f"Please choose an option from {valid_ans_list}")


# Main routine goes here
pizza_sizes = ['small', 'medium', 'large']

like_coffee = string_check("Would you like a pizza? 🍕 ", ['yes', 'no'])
chosen_size = string_check("Choose a size: ", pizza_sizes)