[1] https://github.com/earwig/mwparserfromhell/archive/develop.zip
At this stage, it might be best to use stable releases [1] instead of the development version, so you'd want [2] (or [3], which will always point to the latest version).
Also, as a note, the parser only supports Python 2.7 and 3, not Python 2.6. Is it worth extending compatibility to 2.6?
[1] https://github.com/earwig/mwparserfromhell/releases [2] https://github.com/earwig/mwparserfromhell/archive/v0.2.zip [2] https://github.com/earwig/mwparserfromhell/archive/master.zip
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