save project

my_game.py

@@ -55,6 +55,7 @@ while True:
         index=index+1
         if  index>= 4:
             index=0
+        screen.blit(background)
     if rest.x <0-rest.width:
         zhangai=random.choice([stone,apple,cacti])  
         rest=zhangai.get_rect()