auto save

2.py

+import pygame as a
+from pygame import locals as b
+a.init()
+screen=a.display.set_mode()
+a.display.set_caption('demo')
+bg=a.image.load('bg.png')
+while True:
+    for event in a.event.get():
+        if event.type == b.QUIT:
+            exit()
+a=screen.blit(bg,(0,0))
+pygame.display.update()
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