protobuff supports 3.0 (though apparently the pip3 version still requires you to manually run 2to3, but then it works) and there's already a port of fabric (ish) by the original author to py3. And Ansible should be python2 until distros start shipping py3 by default, (which they have so I assume Ansible3 will come out soonTM).

If you're willing to do a bit more than "pip install x", well I guess it doesn't work, back to py2, you can use almost everything on py3. (and yes requests is ported too)