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Changes between Version 1 and Version 2 of Ticket #33579, comment 7

v1	v2
1	1	Another alternative we would be to simply raise a `cls.DoesNotExists` error instead.
2	2
3		It would be backward incompatible in the sense that a different exception type would be raised but it seems it would fit elegantly with the message it's meant to convey; the object that was attempted to be updated was not found. It would also make code that handles generic `DoesNotExist` and turn them into HTTP 404 automatically pick up errors of this form without any ~~form of~~ special casing.
	3	It would be backward incompatible in the sense that a different exception type would be raised but it seems it would fit elegantly with the message it's meant to convey; the object that was attempted to be updated was not found. It would also make code that handles generic `DoesNotExist` and turn them into HTTP 404 automatically pick up errors of this form without any special casing.
4	4
5	5	Another argument for this approach is that the affected ''base'' is already available from `Model._save_table` via the `cls` kwarg so it would also allow to differentiate which model row was missing when dealing with concrete model inheritance that require update against multiple tables.