This answer on Stack Overflow might be a good starting point.

We could add the following rules (https://github.com/sbousseaden/YaraHunts) to the default Yara rules available

Hi all,

username check with reddit.com is yet to be done. As it has a landing page for broken url, page need to be fetched and analyzed for membership. Base code available in the file 'test_.py' file. Appreciate any help.

Thanks.
-rahul