how to apply gradient clipping in TensorFlow when distributed training?

Question

I would like to know how to apply gradient clipping in TensorFlow when distributed training. Here's my code:

    @lazy_property
    def optimize(self):
        # train_vars = ...
        optimizer = tf.train.AdamOptimizer(self._learning_rate)
        self.syn_op = tf.train.SyncReplicasOptimizer(optimizer,
                                                     replicas_to_aggregate=self.gradient_merge,
                                                     total_num_replicas=self.worker_count,
                                                     use_locking=True)
        self.sync_replicas_hook = self.syn_op.make_session_run_hook(is_chief=self.is_chief)
        return self.syn_op.minimize(self.cost, var_list=train_vars, global_step=self.global_step)

I've read this answer: How to apply gradient clipping in TensorFlow. Here is the code of gradient clip in the answer:

        optimizer = tf.train.AdamOptimizer(learning_rate=learning_rate)
        gvs = optimizer.compute_gradients(cost)
        capped_gvs = [(tf.clip_by_value(grad, -1., 1.), var) for grad, var in gvs]
        train_op = optimizer.apply_gradients(capped_gvs)

Where should I change to use it in my condition?