code: def getSrcBlocks(self, url, dataset="", block=""):
          
          if block:
              params={'block_name':block, 'open_for_writing':0}
          elif dataset:
              params={'dataset':dataset, 'open_for_writing':0}
          else:
              m = 'DBSMigration: Invalid input.  Either block or dataset name has to be provided'
              e = 'DBSMigrate/getSrcBlocks: Invalid input.  Either block or dataset name has to be provided'
              dbsExceptionHandler('dbsException-invalid-input2', m, self.logger.exception, e )
  
          return cjson.decode(self.callDBSService(url, 'blocks', params, {}))
docs: Need to list all blocks of the dataset and its parents starting from the top
          For now just list the blocks from this dataset.
          Client type call...