From 2369759a47c5292bacf2eef17b4e2388b7d36675 Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Sun, 15 Nov 2020 17:52:22 -0800
Subject: [PATCH] bpo-42317: Improve docs of typing.get_args concerning Union
 (GH-23254)

(cherry picked from commit c3b9592244a9112d8af9610ff1c4e1e4cd4bfaca)

Co-authored-by: Dominik1123 <15989985+Dominik1123@users.noreply.github.com>
---
 Doc/library/typing.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst
index a5f8b0403f8..324abdeb5eb 100644
--- a/Doc/library/typing.rst
+++ b/Doc/library/typing.rst
@@ -1687,6 +1687,9 @@ Introspection helpers
    For a typing object of the form ``X[Y, Z, ...]`` these functions return
    ``X`` and ``(Y, Z, ...)``. If ``X`` is a generic alias for a builtin or
    :mod:`collections` class, it gets normalized to the original class.
+   If ``X`` is a :class:`Union` contained in another generic type,
+   the order of ``(Y, Z, ...)`` may be different from the order of
+   the original arguments ``[Y, Z, ...]`` due to type caching.
    For unsupported objects return ``None`` and ``()`` correspondingly.
    Examples::