docs: def prep(s, p, o):
      '''
      Prepare a triple for rdflib
      '''
      def bnode_check(r):
          return isinstance(r, mock_bnode) or r.startswith('VERSABLANKNODE_')
  
      s = BNode() if bnode_check(s) else URIRef(s)
      p = URIRef(p)
      o = BNode() if bnode_check(o) else (URIRef(o) if isinstance(o, I) else Literal(o))
      return s, p, o