TIC TAC TOE FINAL

tictactoe.py

board=[' ' for x in range(9)]
#legal board values = X,O
board[4] = 'X'
winning=False

def player_move():
    global winning
    pos = input("Enter your move ")
    board[pos] = 'O'
    winning = checkwin('O')

def computer_move():
    global winning, board
    possible_moves = []
    for i in range(len(board)):
        if board[i] == ' ':
            possible_moves.append(i)
    possible_moves_scores = []
    for j in possible_moves:
        possible_moves_scores.append(get_score(board, j))
    correct_move = possible_moves[possible_moves_scores.index(min(possible_moves_scores))]
    board[correct_move] = 'X'
    winning=checkwin('X')
    possible_moves=[]
    possible_moves_scores=[]

def get_score(board, i):
    score=0
    copy_board = [x for x in board]
    copy_board[i] = 'X'
    directory = {
            ' ': 1,
            'X': 2,
            'O': 0
        }
    score+=directory[board[i]]+directory[board[(i+3)%9]]+directory[board[(i+6)%9]] #same column
    if i==0 or i==2 or i==1:
        score+=directory[board[0]] + directory[board[1]] + directory[board[2]]
    if i==3 or i==4 or i==5:
        score+=directory[board[3]] + directory[board[4]] + directory[board[5]]
    if i==6 or i==7 or i==8:
        score+=directory[board[6]] + directory[board[7]] + directory[board[8]]
    #diagonals
    '''if i==0 or i==8:
        score+=directory[board[0]] + directory[board[8]] + directory[board[4]]
    if i==2 or i==6:
        score+=directory[board[2]] + directory[board[4]] + directory[board[6]] '''
    return score

def printboard():
    print board[0]+"|"+board[1] + "|"+board[2]
    print "-----"
    print board[3]+"|"+board[4] + "|"+board[5]
    print "-----"
    print board[6]+"|"+board[7] + "|"+board[8]
    print '-----------------------'

def checkwin(player):
    return ((board[0]==board[1]==board[2]==player) or (
            board[3]==board[4]==board[5]==player) or (
            board[6]==board[7]==board[8]==player) or (
            board[0]==board[3]==board[6]==player) or (
            board[1]==board[4]==board[7]==player) or (
            board[2]==board[5]==board[8]==player) or (
            board[0]==board[4]==board[8]==player) or (
            board[2]==board[4]==board[6]==player))

def movesremaining():
    return ' ' in board

def is_even(num):
    return num%2 == 0

printboard()

turn = 0

while True:
    if is_even(turn) and movesremaining():
        player_move()
        printboard()
        if winning:
            print 'player wins'
            break
    elif not is_even(turn) and movesremaining():
        print 'computer plays'
        computer_move()
        printboard()
        if winning:
            print 'computer wins'
            break
    else:
        print 'draw'
        break
    turn+=1