[pygame] strange about pygame.image.save

["jaleco" <jaleco@svr1.gameone.com.tw>]

if I wrote this:

   pygame.image.save(screen,"snapshot.bmp")

 

Traceback (most recent call last):
  File "opengl0.py", line 70, in ?
    if __name__ == '__main__': main()
  File "opengl0.py", line 63, in main
    pygame.image.save(screen,"snapshot.bmp")
TypeError: argument 1 must be string, not Surface

 

and I change it :

   pygame.image.save("snapshot.bmp",screen)

  

C:\One\Source\pytest>python opengl0.py
Traceback (most recent call last):
  File "opengl0.py", line 70, in ?
    if __name__ == '__main__': main()
  File "opengl0.py", line 63, in main
    pygame.image.save("snapshot.bmp",screen)
TypeError: argument 1 must be Surface, not string