Issue #24254: Preserve class attribute definition order.
diff --git a/Lib/typing.py b/Lib/typing.py
index 5573a1f..5f451b0 100644
--- a/Lib/typing.py
+++ b/Lib/typing.py
@@ -1301,6 +1301,7 @@
                     if (not attr.startswith('_abc_') and
                             attr != '__abstractmethods__' and
                             attr != '_is_protocol' and
+                            attr != '__definition_order__' and
                             attr != '__dict__' and
                             attr != '__args__' and
                             attr != '__slots__' and