code: def listFileParents(self, logical_file_name='', block_id=0, block_name=''):
          
          try:
              r = self.dbsFile.listFileParents(logical_file_name, block_id, block_name)
  	    for item in r:
  		yield item	
          except HTTPError as he:
  	    raise he
          except dbsException as de:
              dbsExceptionHandler(de.eCode, de.message, self.logger.exception, de.serverError)
          except Exception as ex:
              sError = "DBSReaderModel/listFileParents. %s\n. Exception trace: \n %s" \
                      % (ex, traceback.format_exc())
              dbsExceptionHandler('dbsException-server-error', ex.message,  self.logger.exception, sError)
docs: API to list file parents
  
          :param logical_file_name: logical_file_name of file (Required)
          :type logical_file_name: str, list
          :param block_id: ID of the a block, whose files should be listed
          :type block_id: int, str
          :param block_name: Name of the block, whose files should be listed
          :type block_name: int, str
          :returns: List of dictionaries containing the following keys (parent_logical_file_name, logical_file_name)
          :rtype: list of dicts