import tensorflow as tf

    gfile.MakeDirs(save_dir)

    with tf.Session(
        target="",
        config=tf.ConfigProto(device_count={"CPU": 2})) as sess:
      with sess.graph.device("/cpu:0"):
        v0 = tf.Variable(111, name="v0")
      with sess.graph.device("/cpu:1"):
        v1 = tf.Variable(222, name="v1")
      save = tf.train.Saver({"v0": v0, "v1": v1}, sharded=True, max_to_keep=2)
      tf.initialize_all_variables().run()
      self.assertEqual([], save.last_checkpoints)

      s1 = save.save(sess, os.path.join(save_dir, "s1"))
      self.assertEqual([s1], save.last_checkpoints)
      self.assertEqual(2, len(gfile.Glob(s1)))
      self.assertTrue(gfile.Exists(save._MetaGraphFilename(s1)))

