Changed assertIsNotNone to assertFalse
Changed assertIsNotNone to assertFalse

assertIsNotNone is not compatible with Python < 2.7

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