def _restore_vars(self, sess):
    '\n        :param sess:\n        :return: boolean for successful or not\n        '
    if (not self._restore_optimistic):
        if (self.restore_ckpt_file is None):
            logger.warn(Color.yellow('No checkpoint file for restore vars, checkpoint file is None', bold=True))
            return False
        self._restore_saver = tf.train.Saver(self._var_list, name='tk_restore')
        self._restore_saver.restore(sess, self.restore_ckpt_file)
        return True
    else:
        return self._optimistic_restore_model(sess)
:param sess:
:return: boolean for successful or not
def _restore_vars(self, sess):
    '\n        :param sess:\n        :return: boolean for successful or not\n        '
    if (not self._restore_optimistic):
        if (self.restore_ckpt_file is None):
            logger.warn(Color.yellow('No checkpoint file for restore vars, checkpoint file is None', bold=True))
            return False
        self._restore_saver = tf.train.Saver(self._var_list, name='tk_restore')
        self._restore_saver.restore(sess, self.restore_ckpt_file)
        return True
    else:
        return self._optimistic_restore_model(sess)