Refs #33476 -- Reformatted code with Black.

tests/select_related_onetoone/models.py

@@ -70,7 +70,9 @@ class Child4(Child1):
 class LinkedList(models.Model):
     name = models.CharField(max_length=50)
     previous_item = models.OneToOneField(
-        'self', models.CASCADE,
-        related_name='next_item',
-        blank=True, null=True,
+        "self",
+        models.CASCADE,
+        related_name="next_item",
+        blank=True,
+        null=True,
     )