Where in the menus?

from gimpfu import *

def do_stuff(img, layer, howmuch) :
    pdb.gimp_invert(layer)

register("python_fu_do_stuff",
	 "Do stuff", "Do some neat stuff",
	 "Your Name", "Your Name", "2008",
	 "Do Stuff...",
	 "RGB*",
	 [ (PF_INT, "amt", "How much?", 50) ]
	 [],       # return vals, seldom used
	 do_stuff,
         menu="<Image>/Filters/Enhance")

main()