Adding own libraries in Sikuli 0.10

I'm working on a project for testing a GUI. I've got a bunch of tests that look like this:

def test001 ():
 doSomething...

The problem is that I don't want all the tests to reside in the main script, because it would make modifying the tests very difficult (there will be close to 100 tests when I'm done). What I'd like is to have each test as a separate file or folder, and then call the test I want from the main script.

I've tried exporting executables and running those from Sikuli using Windows Run command, and it works ok, except it introduces the need for some pauses and connecting elements in the script, because the GUI loses focus when using the Run command, and reacts differently to every switchApp(...) command. This makes testing unpredictable and unreliable.

Also, I don't want to use the unit testing feature for reasons I can't share at the moment.

I was thinking along the lines of custom libraries that I can import into Sikuli, but I have no idea how to create them.

Any help/idea will be greatly appreciated.