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
36426	prefetch_related_objects() is doc'd to accept iterables but only accepts sequences	Jacob Walls		"The docs say `prefetch_related_objects()` [https://docs.djangoproject.com/en/5.2/ref/models/querysets/#django.db.models.prefetch_related_objects accepts iterables], but it only accepts sequences.

{{{#!py
In [1]: from django.db.models import prefetch_related_objects

In [2]: objs = set(Graph.objects.all())

In [3]: prefetch_related_objects(objs, ""node_set"")
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[3], line 1
----> 1 prefetch_related_objects(objs, ""node_set"")

File ~/py313/lib/python3.13/site-packages/django/db/models/query.py:2361, in prefetch_related_objects(model_instances, *related_lookups)
   2355     break
   2357 # Descend down tree
   2358 
   2359 # We assume that objects retrieved are homogeneous (which is the premise
   2360 # of prefetch_related), so what applies to first object applies to all.
-> 2361 first_obj = obj_list[0]
   2362 to_attr = lookup.get_current_to_attr(level)[0]
   2363 prefetcher, descriptor, attr_found, is_fetched = get_prefetcher(
   2364     first_obj, through_attr, to_attr
   2365 )

TypeError: 'set' object is not subscriptable
}}}

We could adjust the docs, but at a glance we could probably instead adjust the implementation to just `next()` instead of `[0]` and accept iterables as documented.

django-stubs [https://github.com/typeddjango/django-stubs/blob/5bb841674610e88a162475b7ecf2e950a92c23a8/django-stubs/db/models/query.pyi#L247 types] the argument as `Model[Iterable]`."	Bug	new	Database layer (models, ORM)	5.2	Normal				Unreviewed	0	0	0	0	1	0