diff --git a/django/utils/unittest/case.py b/django/utils/unittest/case.py
index a855398bc2..fa0992c19b 100644
--- a/django/utils/unittest/case.py
+++ b/django/utils/unittest/case.py
@@ -898,7 +898,7 @@ class TestCase(unittest.TestCase):
             expected.sort()
             actual = actual_seq[:]
             actual.sort()
-        except TypeError:
+        except (TypeError, AttributeError):
             # Unsortable items (example: set(), complex(), ...)
             expected = list(expected_seq)
             actual = list(actual_seq)