在Python中按住键时更新动画

Question

    # Move the player.
    if moveDown and player.bottom < WINDOWHEIGHT:
        player.top += MOVESPEED
        playerImage = pygame.image.load('PlayerFSprite1.png')
        playerStretchedImage = pygame.transform.scale(playerImage, (256, 256))
        windowSurface.blit(playerStretchedImage, player)

    if moveUp and player.top > 0:
        player.top -= MOVESPEED
        playerImage = pygame.image.load('Player USprite.png')
        playerStretchedImage = pygame.transform.scale(playerImage, (256, 256))
        windowSurface.blit(playerStretchedImage, player)

    if moveLeft and player.left > 0:
        player.left -= MOVESPEED
        playerImage = pygame.image.load('PlayerLSprite.png')
        playerStretchedImage = pygame.transform.scale(playerImage, (256, 256))
        windowSurface.blit(playerStretchedImage, player)

    if moveRight and player.right < WINDOWWIDTH:
        player.right += MOVESPEED
        playerImage = pygame.image.load('PlayerRSprite.png')
        playerStretchedImage = pygame.transform.scale(playerImage, (256, 256))
        windowSurface.blit(playerStretchedImage, player)

这段代码正在使精灵移动一个具有特定动画的方向，但我想知道如何在按住键方向的同时让动画切换到另一个动画，这样当拿着＆＃34; W＆＃34;将有第一个动画，然后在0.2秒延迟后出现另一个动画。