python贪吃蛇核心功能实现下

#创建一条新的蛇
def create_new_snake():
    snake_body = []
    snake_x = random.randint(5, rows - 5)
    snake_y = random.randint(5, columns - 5)
    snake_body.append([snake_x, snake_y])
    snake_body.append([snake_x, snake_y + 1])
    snake_body.append([snake_x, snake_y + 2])
    return snake_body

snake = create_new_snake()

def create_new_apple(snake_body):
    apple_in_game = False
    while not apple_in_game:
        apple_x = random.randint(0, rows - 1)
        apple_y = random.randint(0, columns - 1)
        # print(apple_x, apple_y)
        if (apple_x, apple_y) not in snake_body:
            new_apple = pygame.image.load('apple.png')
            new_apple = pygame.transform.scale(new_apple, (tile_size - 2, tile_size - 2))
            apple_x_location = apple_y * tile_size + x_margin/2
            apple_y_location = apple_x * tile_size + y_margin/2

            display.blit(new_apple, (apple_x_location, apple_y_location))
            apple_in_game = True
    return new_apple, (apple_x, apple_y), apple_x_location, apple_y_location

if __name__ == '__main__':
    pygame.init()
    snake = create_new_snake()
    # 未按下按键时，默认的初识移动方向
    direction = directions[random.randint(0, 3)]
    # 创建一个小苹果
    apple, apple_location, apple_left, apple_top = create_new_apple(snake)
    # 吃到苹果标志
    apple_was_eaten = False

        if apple_location in snake:
            apple, apple_location, apple_left, apple_top = create_new_apple(snake)
            apple_was_eaten = True
            my_score += 1

        if snake[0] in snake[1:]:
            snake = create_new_snake()
            #print(snake)
        elif is_right_direction(snake, new_body_location[0], new_body_location[1]):
            snake.insert(0, new_body_location)
            if not apple_was_eaten:
                del snake[-1]
            else:
                apple_was_eaten = False

#游戏结束时特效
def game_over_animation(color=white, animation_speed=50):
    orig_surf = display.copy()
    flash_surf = pygame.Surface(display.get_size())
    flash_surf = flash_surf.convert_alpha()
    r, g, b = color
    for i in range(3):
        for start, end, step in ((0, 255, 1), (255, 0, -1)):
            for alpha in range(start, end, animation_speed * step):
                # 先铺一层新的界面，包含老界面所有内容
                display.blit(orig_surf, (0, 0))
                # flash界面填充颜色，开始很淡，越来越浓，然后越来越淡
                flash_surf.fill((r, g, b, alpha))
                # 把flash界面加载到display中
                display.blit(flash_surf, (0, 0))
                # draw_game_board(maze)
                # 刷新看效果
                pygame.display.update()
                fps_clock.tick(fps)

def make_score():
    score = pygame.font.Font('Kaiti.ttc', 20)
    score_surf = score.render('得分: %d' % my_score, True, text_color, bg_color)
    score_rect = score_surf.get_rect()
    score_rect.topleft = (screen_width-100, y_margin/8)
    return score_surf, score_rect