Add missing 'versionadded' for shlex.quote; closes #14165
diff --git a/Doc/library/shlex.rst b/Doc/library/shlex.rst
index 908f996..941e090 100644
--- a/Doc/library/shlex.rst
+++ b/Doc/library/shlex.rst
@@ -66,6 +66,7 @@
       >>> command
       ['ls', '-l', 'somefile; rm -rf ~']
 
+   .. versionadded:: 3.3
 
 The :mod:`shlex` module defines the following class: