def export(self,
             estimator,
             export_path,
             checkpoint_path,
             eval_result,
             is_the_final_export=None):
    """Actually performs the export of registered Modules."""
    if self._best_eval_result is None or self._compare_fn(
        best_eval_result=self._best_eval_result,
        current_eval_result=eval_result):
      tf.logging.info("Exporting the best modules.")
      self._best_eval_result = eval_result
      return self._latest_module_exporter.export(estimator, export_path)
Actually performs the export of registered Modules.
language/common/utils/exporters.py