bug again

Traceback (most recent call last):
  File "extras/pokemontools/gfx.py", line 1669, in <module>
    main()
  File "extras/pokemontools/gfx.py", line 1665, in main
    method(args.filenames)
  File "extras/pokemontools/gfx.py", line 1593, in convert_to_2bpp
    export_png_to_2bpp(filename)
  File "extras/pokemontools/gfx.py", line 1261, in export_png_to_2bpp
    image, palette, tmap = png_to_2bpp(filein, **arguments)
  File "extras/pokemontools/gfx.py", line 1330, in png_to_2bpp
    assert len(palette) <= 4, 'Palette should be 4 colors, is really %d' % len(palette)
AssertionError: Palette should be 4 colors, is really 5
Makefile:56: recipe for target 'gfx/pics.o' failed
make: *** [gfx/pics.o] Error 1