I assume you're using GIMP?
Just hazarding a guess, but you probably have to get the package by running the command 'pit install python-fu' - I've only interacted with the GUI side of GIMP for the most part so I couldn't tell you the first thing about python-fu, other than the fact it should be relatively straightforward.
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"Standing on a well-chilled cinder, we see the fading of the suns, and try to recall the vanished brilliance of the origin of the worlds."
-Georges Lemaitre
"I fly through hyperspace, in my green computer interface"
-Gem Tos
