The repo with slides and exercises: https://github.com/ASPP/testing_debugging_profiling
Direct link to slides: https://github.com/ASPP/testing_debugging_profiling/raw/master/testing-debugging-profiling.pdf
Etherpad: https://public.etherpad-mozilla.org/p/aspp
Context manager help: http://www.scipy-lectures.org/advanced/advanced_python/index.html#context-managers