You can create GUI tests with SikuliX in a blink. There is a default IDE, but if you want to write python tests for SikuliX in your favorite editor, here is my Sublime Text package.

To activate it, follow the instructions on the SikuliTools Project Page.

Currently the SikuliTools support capturing a selection from the screen, saving it to the currently active directory and inserting the filename at the cursor position.