Hangman game help please =D

import sys                           # import usually at top of script
import random

# otherwise fail as soon as possible
if not input('Press ENTER to exit or type in anything to play\n'):
    sys.exit(0)

HANGMAN = range(7) or (pic1, pic2, pic3, pic4, pic5, pic6, pic7)
# ^Some ASCII art i made to show the noose and the stick man

# let's not make case of the letter an issue.  use lower case.
WORDS = 'bunch of random words'.lower().split()

word = random.choice(WORDS)
wrongGuesses = 0
guesses = set()                  # set is better data type

def substitutions(a,s,fill):
    '''
        a is an iterable with len method.
        s is an object supporting the __contains__ method
        fill is any object.

        returns a list of length len(a) which has the fill value
        substituted for any item of a not in s.


        Learn also to write a function,
        Learn to write a function of general use,
        Learn to use doctest.

        $ python3 -m doctest this_file.py  # unix command

        >>> # examples of our sterling substitutions function
        >>> substitutions(list(range(8))+[4],set((4,3,),),666)
        [666, 666, 666, 3, 4, 666, 666, 666, 4]
        >>> substitutions('mississippi',set('xsuzp'),'_')
        ['_', '_', 's', 's', '_', 's', 's', '_', 'p', 'p', '_']
        >>> ''.join(substitutions('mississippi',set('xsuzp'),'_'))
        '__ss_ss_pp_'
        >>>
    '''
    result = []
    for i in a:
        result.append(i if i in s else fill)
    return result

while wrongGuesses != 6:
    print(HANGMAN[wrongGuesses],''.join(substitutions(word,guesses,'_')))
    guess = (input('Guess a letter')+' ')[0].lower() # one letter at a time.
    if guess in guesses:
        print('You already guessed that letter')
    else:
        guesses.add(guess)
        if guess not in word:
            print('That letter is not in the word')
            wrongGuesses += 1
        else:
            print('more logic needed to determine final victory')