The prefered style of the titles in HN is more dry. The guidelines [1] ask to use the origianl title, but sometimes it's too bad and the subtitle is a good alternative. If you repost it, my sugestion is to use a reduced version of the first sentence "Niquests is a simple, yet elegant, HTTP library. It is a drop-in replacement for Requests that is no longer under feature freeze.", something like "Niquests: A HTTP library for Python that is a drop-in replacement for Requests"

[1] https://news.ycombinator.com/newsguidelines.html