code: def query_parent_objects(self, context, query=None):
          
  
          # return the object values if we have no catalog query
          if query is None:
              return self.get_parent_objects(context)
  
          # avoid undefined reference of catalog in except...
          catalog = None
  
          # try to fetch the results via the catalog
          try:
              catalogs = api.get_catalogs_for(context)
              catalog = catalogs[0]
              return map(api.get_object, catalog(query))
          except (IndexError, UnicodeDecodeError, ParseError, APIError) as e:
              # fall back to the object values of the parent
              logger.warn("UniqueFieldValidator: Catalog query {} failed "
                          "for catalog {} ({}) -> returning object values of {}"
                          .format(query, repr(catalog), str(e),
                                  repr(api.get_parent(context))))
              return self.get_parent_objects(context)
docs: Return the objects of the same type from the parent object
  
          :param query: Catalog query to narrow down the objects
          :type query: dict
          :returns: Content objects of the same portal type in the parent