Fix storing bytes literals in Python 3.
Fix storing bytes literals in Python 3.

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