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Changes between Initial Version and Version 1 of Ticket #27001, comment 3

initial	v1
1	1	Created a pull request with a fix.
2	2
3		`ChoiceFieldRenderer` doesn't have `__iter__` defined, so Python iterates over it by calling `__getitem__` with an increasing index until an exception is raised. `ChoiceFieldRenderer.__getitem__` calls `list` on itself, which turns iteration into an n^2 operation. When the choices are backed by a queryset as in ModelChoiceField, that means lots of redundant database queries.
	3	`ChoiceFieldRenderer` doesn't have `__iter__` defined, so Python iterates over it by calling `__getitem__` with an increasing index until an exception is raised. `ChoiceFieldRenderer.__getitem__` calls `list` on itself, which turns iteration into an n^2^ operation. When the choices are backed by a queryset as in ModelChoiceField, that means lots of redundant database queries.
4	4
5	5	Fixed by adding an `__iter__` method to `ChoiceFieldRenderer` and changing `__getitem__` to use it, so that indexing still works.