Ensure that you have run the initializer operation for this iterator before getting the next element

[JunGenius]

Hello, {"GetNext() failed because the iterator has not been initialized. Ensure that you have run the initializer operation for this iterator before getting the next element.\n\t [[{{node ds/next}} = IteratorGetNextoutput_shapes=[[?,48000], [?,2]], output_types=[DT_FLOAT, DT_FLOAT], _device="/job:localhost/replica:0/task:0/device:CPU:0"]]"}

` C#

   var runner = _session.GetRunner();          

        runner.AddInput(_graph["ph/frames"][0], x)
                .AddInput(_graph["ph/labels"][0], y)
                .AddInput(_graph["ph/n_shuffle"][0], ph_n_shuffle)
                .AddInput(_graph["ph/n_repeat"][0], ph_n_repeat)
                .AddInput(_graph["ph/n_batch"][0], ph_n_batch)
                .Fetch(_graph["net/layers/logits/dense/Softmax"][0]);

        var output = runner.Run();

`

`

Python:

  with graph.as_default():

    saver = tf.train.import_meta_graph(checkpoint_path + '.meta')

    x = graph.get_tensor_by_name(vocab['x'])
    y = graph.get_tensor_by_name(vocab['y'])
    init = graph.get_operation_by_name(vocab['init'])
    logits = graph.get_tensor_by_name(vocab['logits'])
    ph_n_shuffle = graph.get_tensor_by_name(vocab['n_shuffle'])
    ph_n_repeat = graph.get_tensor_by_name(vocab['n_repeat'])
    ph_n_batch = graph.get_tensor_by_name(vocab['n_batch'])
    sr = vocab['sample_rate']

    with tf.Session() as sess:

        saver.restore(sess, checkpoint_path)

        for file in files:

            print('processing {}'.format(file), flush=True)

            if os.path.exists(file):
                sound, _ = audio_from_file(file, sr=sr)
                input = audio_to_frames(sound, x.shape[1])
                labels = np.zeros((input.shape[0],), dtype=np.int32)
                sess.run(init,
                         feed_dict={x: input, y: labels, ph_n_shuffle: 1, ph_n_repeat: 1, ph_n_batch: n_batch})
                count = 0
                n_total = input.shape[0]
                while True:
                    try:
                        output = sess.run(logits)
                        labels[count:count + output.shape[0]] = np.argmax(output, axis=1)
                        count += output.shape[0]
                        print('{:.2f}%\r'.format(100 * (count / n_total)), end='', flush=True)
                    except tf.errors.OutOfRangeError:
                        break
                noise = input[np.argwhere(labels == 0), :].reshape(-1, 1)
                speech = input[np.argwhere(labels == 1), :].reshape(-1, 1)
                name, ext = os.path.splitext(file)
                audio_to_file(os.path.join(name + '.speech' + ext), speech, sr)
                audio_to_file(os.path.join(name + '.noise' + ext), noise, sr)

            else:
                print('skip [file not found]')

` how to initialize an iterator？Thank you very much.