Wxpython is accessible, to a point. Functions like the aui branch aren't accessible, and sussing out which ones are and aren't throughout can be a bit of a trial and error experience, depending on what you want to do. I think PyQT might be another option? There's also Pygame and Pyglet, but their screen output is not natively accessible, so you'd have to hook in something like Tolk or pyttsx for tts support. Kivy might also be another option, though I haven't had an opportunity to test it for accessibility, so it may be like Pygame and Pyglet.