docs: def parse_rdf(self):
          """ Parses the relevant PG rdf file
          """
          try:
              self.metadata = pg_rdf_to_json(self.rdf_path)
          except IOError as e:
              raise NoRDFError(e)
  
          if not self.authnames():
              self.author = ''
          elif len(self.authnames()) == 1:
              self.author = self.authnames()[0]
          else:
              self.author = "Various"