The Secure Sockets layer is only actually secure if you check the hostname in the certificate returned by the server to which you are connecting, and verify that it matches to hostname that you are trying to reach. But the matching logic, defined in RFC2818, can be a bit tricky to implement on your own. So the ssl package in the Standard Library of Python 3.2 now includes a match_hostname function for performing this check instead of requiring every application to implement the check separately. This backport brings match_hostname to users of earlier versions of Python. The actual code inside comes verbatim from Python 3.2.