skinnable, portable widgets?

[Brandon Van Every]

I'm looking for a GUI widget toolkit that:
- has a python binding
- is skinnable
- is portable/ported to at least Win32 and Linux
- does not try to own the application's event pump
- is amenable to displaying my own 3D code in a window
- is mature, ready for prime time
- is open source
- whose implementation is not overly complicated, so that as things bitrot
over the next 10 years, I can maintain it and port it to new platforms

The primary application is for games.  I must be able to control the look
and feel of the widgets, so skinnability is a hard requirement.  Any
recommendations?


--
Cheers,                         www.3DProgrammer.com
Brandon Van Every               Seattle, WA

20% of the world is real.
80% is gobbledygook we make up inside our own heads.