From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Thu, 11 Jun 2026 06:38:03 +0000 (+0200)
Subject: [3.15] gh-136880: Add warning about PYTHONPATH (GH-151098) (GH-151299)
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=f3316ca675fada57bdf862d7e3aebfd6bb5ac02c;p=thirdparty%2FPython%2Fcpython.git

[3.15] gh-136880: Add warning about PYTHONPATH (GH-151098) (GH-151299)

(cherry picked from commit 84630e2cb90ef334e41eb9bccd860b3b0a7ff51b)
---

diff --git a/Doc/tutorial/venv.rst b/Doc/tutorial/venv.rst
index f362e1943b66..6b6b8a768e3f 100644
--- a/Doc/tutorial/venv.rst
+++ b/Doc/tutorial/venv.rst
@@ -88,6 +88,11 @@ For example:
   '~/envs/tutorial-env/lib/python3.5/site-packages']
   >>>
 
+Note that the activated virtual environment does not alter the ``PYTHONPATH`` variable in any way.
+This may lead to unexpected results if the path includes references to code which is incompatible with
+the Python version the virtual environment is using. The best practice is to ``unset PYTHONPATH``
+in bash or the equivalent for the shell you are using.
+
 To deactivate a virtual environment, type::
 
     deactivate