import random

# helper functions

def number_to_name(num):
    if num == 0:
        return 'rock'
    elif num == 1:
        return 'Spock'
    elif num == 2:
        return 'paper'
    elif num == 3:
        return 'lizard'
    else:
        return 'scissors'

    
def name_to_number(name):
   
    if name == 'rock':
        return 0
    elif name == 'Spock':
        return 1
    elif name == 'paper':
        return 2
    elif name == 'lizard':
        return 3
    else:
        return 4
    
# main function

def rpsls(guess):
    
    # convert name to player_number using name_to_number
    
    player_number = name_to_number(guess)
    
    # compute random guess for comp_number using random.randrange()
    
    comp_number = random.randrange(0,5)
    
    # convert comp_number to name using number_to_name
    
    computer_guess = number_to_name(comp_number) 
    
    # compute difference of player_number and comp_number modulo five
    
    result = (player_number - comp_number) % 5
    
    

# use if/elif/else to determine winner    

    if result == 1 or result == 2:
        winner = 'Player wins!'
    elif result == 3 or result == 4:
        winner = 'Computer wins!'
    else:
        winner = 'Player and Computer tie!'

        
# print results

    print
    print 'Player chooses', guess
    print 'Computer chooses', computer_guess
    print winner

    
# test your code
rpsls("rock")
rpsls("Spock")
rpsls("paper")
rpsls("lizard")
rpsls("scissors")

Player chooses rock
Computer chooses rock
Player and Computer tie!

Player chooses Spock
Computer chooses rock
Player wins!

Player chooses paper
Computer chooses scissors
Computer wins!

Player chooses lizard
Computer chooses paper
Player wins!

Player chooses scissors
Computer chooses paper
Player wins!