You must have the rdflib library (rdflib.net) installed in order to
use Zemantic.  It uses disutils so it's quite easy to install.  

After that you install Zemantic with either the distutils installer or
link it into the "lib/python" directory (or anywhere else on your
Python path) of your Zope 3 instance and droping the
"etc/catalog-configure.zcml" into your Zope 3.1 "package-includes".

Restart Zope 3, you shold be able to add an RDF Graph as a local
utility to your sites.