Should we define __round__ on Expression?

[Willem Van Onsem]

Rounding values can be done with:

from django.db.models.functions import Round

Round(Count('related_model'))

But we could also implement the round function on the Expression class, and thus use Python's round(...) function, then it thus no longer requires an import:

round(Count('related_model'))

A potential problem with this is that people might expect that this will itself return a number-like object, and not an expression.

[Simon Charette]

Thanks for the suggestion but I think that sticking to the explicit import makes for a more cohesive expression interface.

I don't think that avoiding an import is a good enough justification to support two ways of achieving a similar result even if we were to adopt this pattern for other magic functions (e.g. __abs__ -> django.db.models.functions.Abs).