A DOI (or "Digital Object Identifier) is a URL-like pointer to a particular permanent object. Astroquery v0.1, released this past week, now has a DOI pointing to the v0.1 tarball hosted on pypi. At this point, the authors include anyone who has contributed a module.

Figshare is the service that is now hosting a clone of the source code and providing the DOI (http://dx.doi.org/10.6084/m9.figshare.805208).

Figshare will generate a new DOI for each new version released, e.g. if we add a new author, release a bugfix tarball, etc. This flexibility makes it preferable to single-version publications like papers and fora. These issues are actively discussed, so feedback is welcome.