@jarun Sorry, I stopped when I noticed the undocumented requests dependency and later forgot about it. I've submitted https://github.com/Homebrew/homebrew-core/pull/21370.
However, I'm not quite convinced about the requests dependency. It's quite trivial to replace the two `requests.post` calls with native `urllib.request`, and the code would still be straightforward; I can even send you a patch. That would help get rid of [all these lines](https://github.com/zmwangx/homebrew-core/blob/8880de373b4c398a231244e9bb6d58b69ae8fa6c/Formula/ddgr.rb#L11-L39) that I'll need to update semi-manually each time.
If you insist on the requests dependency though, I'd say you probably want to actually take advantage of it by using a [session](http://docs.python-requests.org/en/master/user/advanced/#session-objects).
ddgr 1.1 (new formula)
======================
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- [x] Have you built your formula locally with `brew install --build-from-source <formula>`, where `<formula>` is the name of the formula you're submitting?
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Submitting this at the request of a friend.