id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
27880	Use __set_name__ to replace some usages of contribute_to_class.	Simon Charette		"If we were to define [https://docs.python.org/3.6/reference/datamodel.html#object.__set_name__ __set__name__] calling `contribute_to_class()` on `models.Field`, `Manager` and `Options` the following things could be done:

1. `ModelBase.add_to_class` calls could be replaced by simple `setattr(cls, name, value)`.
2. `Options.contribute_to_class` could be inlined in `Options.__set_name__`.
3. `Manager.contribute_to_class` could be inlined in `Manager.__set_name__`.
4. There might be a way to inline `Field.contribute_to_class` by dealing with its `private_only` flag somehow."	Cleanup/optimization	new	Database layer (models, ORM)	dev	Normal		python3.6		Accepted	1	1	1	0	0	0