Consistency with `Final` usage in Standard Library Stubs

Currently usage of typing.Final to indicate constants is mixed throughout the standard library (e.g. some newer stubs will utilize it potentially, but it's left out in other places) Has there been any discussion in the past of experimenting with applying Final to all UPPER_UNDER module stdlib constants?

I think class var constants would require a bit more context on usage, as it might be expected for subclasses to override them, but it could be worth starting with modules and gauging the impact from MyPy primer.

Inizia esaminando l’uso esistente di typing.Final negli stub della libreria standard e qualsiasi discussione precedente a cui fa riferimento l’issue. Usa il MyPy primer per valutare l’impatto dell’applicazione di Final alle costanti a livello di modulo UPPER_UNDER; il lavoro è completato quando vengono concordati una policy chiara e l’ambito dell’implementazione.