RPS.py

import random
import math

def play():
    user = input("What's your choice? 'r' for rock, 'p' for paper, 's' for scissors\n")
    user = user.lower()

    computer = random.choice(['r', 'p', 's'])

    if user == computer:
        return (0, user, computer)

    
    if is_win(user, computer):
        return (1, user, computer)

    return (-1, user, computer)

def is_win(player, opponent):

    if (player == 'r' and opponent == 's') or (player == 's' and opponent == 'p') or (player == 'p' and opponent == 'r'):
        return True
    return False

def play_best_of(n):
    player_wins = 0
    computer_wins = 0
    wins_necessary = math.ceil(n/2)
    while player_wins < wins_necessary and computer_wins < wins_necessary:
        result, user, computer = play()
        if result == 0:
            print('It is a tie. You and the computer have both chosen {}. \n'.format(user))
        elif result == 1:
            player_wins += 1
            print('You chose {} and the computer chose {}. You won!\n'.format(user, computer))
        else:
            computer_wins += 1
            print('You chose {} and the computer chose {}. You lost :(\n'.format(user, computer))

    if player_wins > computer_wins:
        print('You have won the best of {} games! What a champ :D'.format(n))
    else:
        print('Unfortunately, the computer has won the best of {} games. Better luck next time!'.format(n))


if __name__ == '__main__':
    play_best_of(3)