Issue #26638: Mask undefined CLI options to defeat new Sphinx warnings
diff --git a/Doc/distutils/extending.rst b/Doc/distutils/extending.rst
index 5139c6d..501fd7c 100644
--- a/Doc/distutils/extending.rst
+++ b/Doc/distutils/extending.rst
@@ -62,7 +62,7 @@
third-party extensions to provide support for additional packaging systems, but
the commands can be used for anything distutils commands can be used for. A new
configuration option, ``command_packages`` (command-line option
-:option:`--command-packages`), can be used to specify additional packages to be
+:option:`!--command-packages`), can be used to specify additional packages to be
searched for modules implementing commands. Like all distutils options, this
can be specified on the command line or in a configuration file. This option
can only be set in the ``[global]`` section of a configuration file, or before