Lots of Python codebases are on board with that (and I assume codebases in other languages are as well). It's by convention rather than language-level support,

Lots of Python codebases are on board with that (and I assume codebases in other languages are as well). It's by convention rather than language-level support, but works perfectly well: don't bolt business logic onto your ORM classes' methods, handle those elsewhere in a separate layer whose conventions you define. Works great.