save project

snake.py

@@ -61,7 +61,7 @@ while True:
     else:   
         position.pop(0)
     if x<0 or x>630 or y<0 or y >450:
-    exit()    # 将背景图画上去
+        exit()    # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去
     screen.blit(snake_head, position[-1])