Python good for translating GUI built in Java?

[Matthew L. Ginsberg]

My apologies for asking what is surely a well-known question in this
forum.

I've got a GUI application currently written in Java; it's about 16000
lines.  It does a reasonable amount of computation, but Java is such a
badly supported language that I'm thinking about porting it to
something else.  Any language I use should be supported in both
Windows (where my customers are) and linux (where I am).  It needs to
be reasonably fast, and reasonably good at all the usual windows
things -- file selection dialogs, popup menus, image manipulation, etc
etc.

Would Python be a reasonable choice?  Thanks for any advice!

						Matt Ginsberg