Move signal disconnect into finally block

tests/modeltests/delete/tests.py

@@ -233,12 +233,14 @@ class DeletionTests(TestCase):
         def log_post_delete(instance, **kwargs):
             self.assertTrue(R.objects.filter(pk=instance.r_id))
 
-        models.signals.post_delete.connect(log_post_delete, sender=S)
-
         r = R.objects.create(pk=1)
         S.objects.create(pk=1, r=r)
-        r.delete()
 
+        models.signals.post_delete.connect(log_post_delete, sender=S)
+
+        try:
+            r.delete()
+        finally:
             models.signals.post_delete.disconnect(log_post_delete)
 
     @skipUnlessDBFeature("can_defer_constraint_checks")