Fix from_n3 for Python 3.
Fix from_n3 for Python 3.

RDFLib/rdflib,RDFLib/rdflib,ssssam/rdflib,marma/rdflib,avorio/rdflib,dbs/rdflib,dbs/rdflib,yingerj/rdflib,avorio/rdflib,ssssam/rdflib,RDFLib/rdflib,dbs/rdflib,RDFLib/rdflib,avorio/rdflib,yingerj/rdflib,ssssam/rdflib,ssssam/rdflib,marma/rdflib,yingerj/rdflib,dbs/rdflib,yingerj/rdflib,avorio/rdflib,armandobs14/rdflib,armandobs14/rdflib,marma/rdflib,marma/rdflib,armandobs14/rdflib,armandobs14/rdflib