See more info about their safety model in the safety architecture section of this blog post.
https://comma-ai.medium.com/how-to-write-a-car-port-for-open...
But that alone is bloodchilling: it terrifies me, as a pedestrian and cyclist, to think that stuff like this is probably controlling the pieces of machinery that could kill me in a split second.
The safety code has a limit on steering ramp rate and a max torque limit. The driver can easily overpower the torque limit, and the ramp rate limit means it won't suddenly jerk.
The python code I think is temporary, they ultimately want to do end-to-end models that do both perception and control (rather than a model to do perception and traditional controller to do control). If that effort fails I think they would probably replace the python code, the current stuff is definitely amateurish.