code: def getSupportedServices(self, only_uids=True):
          
          uids = map(lambda range: range['uid'], self.getReferenceResults())
          uids = filter(api.is_uid, uids)
          if only_uids:
              return uids
          brains = api.search({'UID': uids}, 'uid_catalog')
          return map(api.get_object, brains)
docs: Return a list with the services supported by this reference sample,
          those for which there is a valid results range assigned in reference
          results
          :param only_uids: returns a list of uids or a list of objects
          :return: list of uids or AnalysisService objects