From dbfc6a417a5db237ff16a8a75f09c1bd5d5bd349 Mon Sep 17 00:00:00 2001
From: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Date: Sun, 6 Apr 2025 05:43:09 -0700
Subject: gh-132139: Document that you can no longer set attributes on unions
 (#132146)

---
 Doc/whatsnew/3.14.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Doc/whatsnew/3.14.rst b/Doc/whatsnew/3.14.rst
index 13448d1..b20d75c 100644
--- a/Doc/whatsnew/3.14.rst
+++ b/Doc/whatsnew/3.14.rst
@@ -1130,6 +1130,8 @@ typing
     For example, ``isinstance(int | str, typing.Union)`` will return ``True``; previously
     this raised :exc:`TypeError`.
   - The ``__args__`` attribute of :class:`typing.Union` objects is no longer writable.
+  - It is no longer possible to set arbitrary dunder attributes on :class:`typing.Union`
+    objects.
 
   (Contributed by Jelle Zijlstra in :gh:`105499`.)
 
-- 
cgit v0.12