Thanks for sharing Bosky.

I think you gave the wrong URL :)

This one talks about how CPython executes a + b: https://codeconfessions.substack.com/p/cpython-dynamic-dispa...

Ow. There's a paywall halfway through. Don't do what I did and get interested in the story if you aren't up to subscribing.

Maybe the reason for CoW being triggered is reference counting. Does anyone know?

Usually from GC. Anthony Sottile has a nice explanatory video: https://youtu.be/sdmcCQ7Em04?si=9PObAJixALFiZ9vd

Sorry about that. Most of my posts are open, but I usually put one of these behind the paywall in a month. I opened this one.