Also add versionchanged directive to the function doc (#11591)
diff --git a/Doc/library/site.rst b/Doc/library/site.rst
index 23ce465..46bd5dc 100644
--- a/Doc/library/site.rst
+++ b/Doc/library/site.rst
@@ -129,6 +129,10 @@
    unless the :program:`python` interpreter was started with the :option:`-S`
    flag.
 
+   .. versionchanged:: 3.3
+      This function used to be called unconditionnally.
+
+
 .. function:: addsitedir(sitedir, known_paths=None)
 
    Adds a directory to sys.path and processes its pth files.