As simple as question is;
What GUI toolkit do you use and why? Why didn't you used the rest?
Here are GUIs I know of:
- TkInter
- PyQT
- PyGTK
- Wxpython
You can Add If you have one that isn't Listed
Atheist: God is man made imagination, he doesn't exist!
Theist: It's okay, can you imagine anything else that doesn't exist?
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Python,
C++ PHP and
Java ----