The kivy tutorial crashcourse from https://kivy.org/docs/tutorials/crashcourse.html.
This code is located here: https://github.com/DaleEMoore/kivy_crash_course.
The person that created this crashcourse has the source code here: https://github.com/inclement/kivycrashcourse.
More information about this kivy crashcourse here: http://inclem.net/pages/kivy-crash-course.