code: def getPropAllSupers(self, aURI):
          
          aURI = aURI
          try:
              qres = self.rdfgraph.query(
                    """SELECT DISTINCT ?x
                       WHERE {
                           { <%s> rdfs:subPropertyOf+ ?x }
                           FILTER (!isBlank(?x))
                       }
                       """ % (aURI))
          except:
              printDebug("... warning: the 'getPropAllSupers' query failed (maybe missing SPARQL 1.1 support?)")
              qres = []
          return list(qres)
docs: note: requires SPARQL 1.1
          2015-06-04: currenlty not used, inferred from above