python方向键控制上下左右代码

bif="1.jpg" mif="2.jpg" import pygame,sys from pygame.locals import *  pygame.init()  screen=pygame.display.set_mode((640,360),0,32) background=pygame.image.load(bif).convert() mouse_c=pygame.image.load(mif).convert_alpha()  x,y=0,0 movex,movey=0,0  while True:   for event in pygame.event.get():     if event.type ==QUIT:       pygame.quit()       sys.exit()     if event.type==KEYDOWN:       if event.key==K_LEFT:         movex=-1       if event.key==K_RIGHT:         movex=+1       elif event.key==K_UP:         movey=-1       elif event.key==K_DOWN:         movey=+1     if event.type==KEYUP:       if event.key==K_LEFT:         movex=0       if event.key==K_RIGHT:         movex=0       elif event.key==K_UP:         movey=0       elif event.key==K_DOWN:         movey=0    x+=movex   y+=movey      screen.blit(background,(0,0))   screen.blit(mouse_c,(x,y))      pygame.display.update()