I've been wishing for that feature for a very long time. It is so much easier for me to paint things in ZBrush than inside Poser, and to be able to GoZ it back to Poser and be asked "Do you want to convert to weight map" would be a dream come true.

As to whether or not that can be done with Python, beats me. I pass out at the sight of a semicolon and coding is not my kind of thing 8-)