[sampo]

> not python

Pandas has a global option to turn on copy-on-write.

https://pandas.pydata.org/docs/dev/user_guide/copy_on_write....

[fbdab103]

News to me! Will definitely break some of my current code (chained assignments no longer work), but is probably a more sensible default.

To be default mode in Pandas 3, but seeing as how long it took them to pull the trigger on Pandas 2, that could be a while.