tacotron_gst.py inference on CPU

python run.py --config_file=example_configs/text2speech/tacotron_gst.py --mode=infer --infer_output_file=unused

*** Building graph on GPU:0
Traceback (most recent call last):
  File "run.py", line 103, in <module>
    main()
  File "run.py", line 78, in main
    args, base_config, config_module, base_model, hvd, checkpoint)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/utils/utils.py", line 883, in create_model
    model.compile(checkpoint=checkpoint)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/models/model.py", line 402, in compile
    self.get_data_layer(gpu_cnt).build_graph()
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/data/text2speech/text2speech.py", line 299, in build_graph
    self._dataset = tf.data.Dataset.from_tensor_slices(self._files)
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/data/ops/dataset_ops.py", line 289, in from_tensor_slices
    return TensorSliceDataset(tensors)
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/data/ops/dataset_ops.py", line 1565, in __init__
    for i, t in enumerate(nest.flatten(tensors))
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/data/ops/dataset_ops.py", line 1565, in <listcomp>
    for i, t in enumerate(nest.flatten(tensors))
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 1050, in convert_to_tensor
    as_ref=False)
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 1146, in internal_convert_to_tensor
    ret = conversion_func(value, dtype=dtype, name=name, as_ref=as_ref)
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/framework/constant_op.py", line 229, in _constant_tensor_conversion_function
    return constant(v, dtype=dtype, name=name)
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/framework/constant_op.py", line 208, in constant
    value, dtype=dtype, shape=shape, verify_shape=verify_shape))
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/framework/tensor_util.py", line 542, in make_tensor_proto
    append_fn(tensor_proto, proto_values)
  File "tensorflow/python/framework/fast_tensor_util.pyx", line 127, in tensorflow.python.framework.fast_tensor_util.AppendObjectArrayToTensorProto
  File "/usr/local/lib/python3.6/site-packages/tensorflow/python/util/compat.py", line 61, in as_bytes
    (bytes_or_text,))
TypeError: Expected binary or unicode string, got nan

Setting "num_gpus": 0 produce another error:

Traceback (most recent call last):
  File "run.py", line 103, in <module>
    main()
  File "run.py", line 78, in main
    args, base_config, config_module, base_model, hvd, checkpoint)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/utils/utils.py", line 882, in create_model
    model = base_model(params=infer_config, mode=args.mode, hvd=hvd)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/models/text2speech.py", line 215, in __init__
    super(Text2Speech, self).__init__(params, mode=mode, hvd=hvd)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/models/encoder_decoder.py", line 76, in __init__
    self._decoder = self._create_decoder()
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/models/encoder_decoder.py", line 102, in _create_decoder
    return self.params['decoder'](params=params, mode=self.mode, model=self)
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/decoders/tacotron2_decoder.py", line 212, in __init__
    self._n_feats = self._model.get_data_layer().params['num_audio_features']
  File "/Users/my_user/external_projects/text-to-speech/OpenSeq2Seq/open_seq2seq/models/model.py", line 901, in get_data_layer
    return self._data_layers[worker_id]
IndexError: list index out of range