removed redundant imports (courtesy Stefano Debenedetti)
removed redundant imports (courtesy Stefano Debenedetti)

git-svn-id: 60eb48102d1ca0c284ab3654bef916b01e1b221b@920 4f84a9ca-5c3e-0410-8a68-0bdf370325d5

nwebs/rdflib