http://cpython-core-tutorial.readthedocs.io/en/latest/
https://github.com/haypo/cpython_core_tutorial

2021
Cristián Maureira-Fredes - Learn CPython by breaking it of 29:30
    https://www.youtube.com/watch?v=CRuXP2jvJ8U
    https://www.youtube.com/watch?v=WThKZDUt_UM