[5.0.x] Fixed #35426 -- Updated querysets to be a required argument of GenericPrefetch.

Backport of 9a27c76021f934201cccf12215514a3091325ec8 from main.

django/contrib/contenttypes/prefetch.py

@@ -3,7 +3,7 @@ from django.db.models.query import ModelIterable, RawQuerySet
 
 
 class GenericPrefetch(Prefetch):
-    def __init__(self, lookup, querysets=None, to_attr=None):
+    def __init__(self, lookup, querysets, to_attr=None):
         for queryset in querysets:
             if queryset is not None and (
                 isinstance(queryset, RawQuerySet)

docs/ref/contrib/contenttypes.txt

@@ -598,7 +598,7 @@ information.
 
 .. versionadded:: 5.0
 
-.. class:: GenericPrefetch(lookup, querysets=None, to_attr=None)
+.. class:: GenericPrefetch(lookup, querysets, to_attr=None)
 
 This lookup is similar to ``Prefetch()`` and it should only be used on
 ``GenericForeignKey``. The ``querysets`` argument accepts a list of querysets,

docs/releases/5.0.5.txt

@@ -30,3 +30,6 @@ Bugfixes
 
 * Fixed a bug in Django 5.0 that caused a migration crash when altering a
   ``GeneratedField`` referencing a renamed field (:ticket:`35422`).
+
+* Fixed a bug in Django 5.0 where the ``querysets`` argument of
+  ``GenericPrefetch`` was not required (:ticket:`35426`).

tests/contenttypes_tests/test_models.py

@@ -333,6 +333,14 @@ class ContentTypesMultidbTests(TestCase):
 
 
 class GenericPrefetchTests(TestCase):
+    def test_querysets_required(self):
+        msg = (
+            "GenericPrefetch.__init__() missing 1 required "
+            "positional argument: 'querysets'"
+        )
+        with self.assertRaisesMessage(TypeError, msg):
+            GenericPrefetch("question")
+
     def test_values_queryset(self):
         msg = "Prefetch querysets cannot use raw(), values(), and values_list()."
         with self.assertRaisesMessage(ValueError, msg):