implement tic tac toe in python

main.py
import random

def draw_board(board):
    print("   |   |")
    print(" "+board[7]+" | "+board[8]+" | "+board[9])
    print("   |   |")
    print("-----------")
    print("   |   |")
    print(" "+board[4]+" | "+board[5]+" | "+board[6])
    print("   |   |")
    print("-----------")
    print("   |   |")
    print(" "+board[1]+" | "+board[2]+" | "+board[3])
    print("   |   |")

def input_player_letter():
    letter = ''
    while not (letter == 'X' or letter == 'O'):
        print("Do you want to be X or O?")
        letter = input().upper()
    if letter == 'X':
        return ['X', 'O']
    else:
        return ['O', 'X']

def who_goes_first():
    if random.randint(0, 1) == 0:
        return 'computer'
    else:
        return 'player'

def make_move(board, letter, move):
    board[move] = letter

def is_winner(bo, le):
    return ((bo[7] == le and bo[8] == le and bo[9] == le) or
    (bo[4] == le and bo[5] == le and bo[6] == le) or
    (bo[1] == le and bo[2] == le and bo[3] == le) or
    (bo[7] == le and bo[4] == le and bo[1] == le) or
    (bo[8] == le and bo[5] == le and bo[2] == le) or
    (bo[9] == le and bo[6] == le and bo[3] == le) or
    (bo[7] == le and bo[5] == le and bo[3] == le) or
    (bo[9] == le and bo[5] == le and bo[1] == le))

def get_board_copy(board):
    board_copy = []
    for i in board:
        board_copy.append(i)
    return board_copy

def is_space_free(board, move):
    return board[move] == ' '

def get_player_move(board):
    move = ''
    while move not in '1 2 3 4 5 6 7 8 9'.split() or not is_space_free(board, int(move)):
        print("What is your next move? (1-9)")
        move = input()
    return int(move)

def choose_random_move_from_list(board, moves_list):
    possible_moves = []
    for i in moves_list:
        if is_space_free(board, i):
            possible_moves.append(i)

    if len(possible_moves) != 0:
        return random.choice(possible_moves)
    else:
        return None

def get_computer_move(board, computer_letter):
    if computer_letter == 'X':
        player_letter = 'O'
    else:
        player_letter = 'X'

    for i in range(1, 10):
        copy = get_board_copy(board)
        if is_space_free(copy, i):
            make_move(copy, computer_letter, i)
            if is_winner(copy, computer_letter):
                return i

    for i in range(1, 10):
        copy = get_board_copy(board)
        if is_space_free(copy, i):
            make_move(copy, player_letter, i)
            if is_winner(copy, player_letter):
                return i

    move = choose_random_move_from_list(board, [1, 3, 7, 9])
    if move != None:
        return move

    if is_space_free(board, 5):
        return 5

    return choose_random_move_from_list(board, [2, 4, 6, 8])

def is_board_full(board):
    for i in range(1, 10):
        if is_space_free(board, i):
            return False
    return True

print("Welcome to Tic Tac Toe!")
while True:
    the_board = [' '] * 10
    player_letter, computer_letter = input_player_letter()
    turn = who_goes_first()
    print("The "+turn+" will go first.")
    game_is_playing = True

    while game_is_playing:
        if turn == 'player':
            draw_board(the_board)
            move = get_player_move(the_board)
            make_move(the_board, player_letter, move)

            if is_winner(the_board, player_letter):
                draw_board(the_board)
                print("Hooray! You have won the game!")
                game_is_playing = False
            else:
                if is_board_full(the_board):
                    draw_board(the_board)
                    print("The game is a tie!")
                    break
                else:
                    turn = 'computer'

        else:
            move = get_computer_move(the_board, computer_letter)
            make_move(the_board, computer_letter, move)

            if is_winner(the_board, computer_letter):
                draw_board(the_board)
                print("The computer has beaten you! You lose.")
                game_is_playing = False
            else:
                if is_board_full(the_board):
                    draw_board(the_board)
                    print("The game is a tie!")
                    break
                else:
                    turn = 'player'

    print("Do you want to play again? (yes or no)")
    if not input().lower().startswith('y'):
        break
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