Backport source links from 3.x.
Existing links have been updated to use the new reST role. In some
files, I have also made cosmetic changes to the header.
diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst
index d93c0d5..bf0899d 100644
--- a/Doc/library/argparse.rst
+++ b/Doc/library/argparse.rst
@@ -4,9 +4,13 @@
.. module:: argparse
:synopsis: Command-line option and argument parsing library.
.. moduleauthor:: Steven Bethard <steven.bethard@gmail.com>
-.. versionadded:: 2.7
.. sectionauthor:: Steven Bethard <steven.bethard@gmail.com>
+.. versionadded:: 2.7
+
+**Source code:** :source:`Lib/argparse.py`
+
+--------------
The :mod:`argparse` module makes it easy to write user-friendly command-line
interfaces. The program defines what arguments it requires, and :mod:`argparse`