code: def get_by_id(self, id, change_notes=False):
          
          graph = uri_to_graph('%s/%s.rdf' % (self.url, id), session=self.session)
          if graph is False:
              log.debug('Failed to retrieve data for %s/%s.rdf' % (self.url, id))
              return False
          # get the concept
          things = things_from_graph(graph, self.subclasses, self.concept_scheme)
          if len(things) == 0:
              return False
          c = things[0]
          return c
docs: Get a :class:`skosprovider.skos.Concept` or :class:`skosprovider.skos.Collection` by id
  
          :param (str) id: integer id of the :class:`skosprovider.skos.Concept` or :class:`skosprovider.skos.Concept`
          :return: corresponding :class:`skosprovider.skos.Concept` or :class:`skosprovider.skos.Concept`.
              Returns None if non-existing id