为了使球拍保持在场地上，请在游戏循环中添加一个复选标记，以在球拍到达边缘时阻止球拍移动。
.......if pong.rect.x < 10: pong.rect.x, pong.rect.y = 375, 250 pong.dx = 1 paddle2.points += 1# keep paddles in correct range # add this sectionif paddle1.rect.y < 0 : paddle1.rect.y = 0if paddle3.rect.y < 0 : paddle3.rect.y = 0if paddle2.rect.y < 200 : paddle2.rect.y = 200if paddle4.rect.y < 200 : paddle4.rect.y = 200if paddle1.rect.y > 200 - 75 : paddle1.rect.y = 200 - 75if paddle3.rect.y > 200 - 75 : paddle3.rect.y = 200 - 75if paddle2.rect.y > 500 - 75 : paddle2.rect.y = 500 - 75if paddle4.rect.y > 500 - 75 : paddle4.rect.y = 500 - 75#if the ball and paddle collide, bounce off itif paddle1.rect.colliderect(pong.rect): pong.dx = 1if paddle2.rect.colliderect(pong.rect): pong.dx = -1.....
