3 (distribute, zc.buildout and pip) only distribute non-version dependent files
leaving just 1 (lxml) with version dependent installers listed at all and it is only for the windows installers.
Drilling down into lxml, roughly 95% of its downloads are the version agnostic .tar.gz file. Also the version dependent installers do not include a 3.3 version but only 3.2 for python3. But even with only an installer for a old version of python3 available it still is >8% of version dependent downloads.