Traceback (most recent call last):
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/ops/array_ops.py", line 3794, in gather_nd
    return params.gather_nd(indices, name=name)
AttributeError: 'SparseTensor' object has no attribute 'gather_nd'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/tensor_util.py", line 558, in make_tensor_proto
    str_values = [compat.as_bytes(x) for x in proto_values]
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/tensor_util.py", line 558, in <listcomp>
    str_values = [compat.as_bytes(x) for x in proto_values]
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/util/compat.py", line 65, in as_bytes
    (bytes_or_text,))
TypeError: Expected binary or unicode string, got <tensorflow.python.framework.sparse_tensor.SparseTensor object at 0x7fab9a39aa90>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "testTrain.py", line 98, in <module>
    train(run_name, 0, 300, 1, 100, 50, 75, 34, 64)
  File "testTrain.py", line 58, in train
    absolute_max_string_len=absolute_max_string_len, output_size=28)
  File "/srv/users/Rifqi/avid/lipnet/testmodel3.py", line 23, in __init__
    self.build()
  File "/srv/users/Rifqi/avid/lipnet/testmodel3.py", line 68, in build
    self.loss_out = CTC('ctc', [self.y_pred, self.labels, self.input_length, self.label_length])
  File "/srv/users/Rifqi/avid/lipnet/core/layers.py", line 14, in CTC
    return Lambda(ctc_lambda_func, output_shape=(1,), name=name)(args)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/keras/engine/base_layer.py", line 489, in __call__
    output = self.call(inputs, **kwargs)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/keras/layers/core.py", line 716, in call
    return self.function(inputs, **arguments)
  File "/srv/users/Rifqi/avid/lipnet/core/loss.py", line 17, in ctc_lambda_func
    return K.ctc_batch_cost(labels, y_pred, input_length, label_length)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/keras/backend/tensorflow_backend.py", line 4484, in ctc_batch_cost
    ctc_label_dense_to_sparse(y_true, label_length), tf.int32)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/keras/backend/tensorflow_backend.py", line 4457, in ctc_label_dense_to_sparse
    vals_sparse = tf.gather_nd(labels, indices)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/util/dispatch.py", line 180, in wrapper
    return target(*args, **kwargs)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/ops/array_ops.py", line 3796, in gather_nd
    return gen_array_ops.gather_nd(params, indices, name=name)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/ops/gen_array_ops.py", line 3991, in gather_nd
    "GatherNd", params=params, indices=indices, name=name)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/op_def_library.py", line 530, in _apply_op_helper
    raise err
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/op_def_library.py", line 527, in _apply_op_helper
    preferred_dtype=default_dtype)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/ops.py", line 1224, in internal_convert_to_tensor
    ret = conversion_func(value, dtype=dtype, name=name, as_ref=as_ref)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/constant_op.py", line 305, in _constant_tensor_conversion_function
    return constant(v, dtype=dtype, name=name)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/constant_op.py", line 246, in constant
    allow_broadcast=True)
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/constant_op.py", line 284, in _constant_impl
    allow_broadcast=allow_broadcast))
  File "/srv/users/Rifqi/avid/lib/python3.5/site-packages/tensorflow/python/framework/tensor_util.py", line 562, in make_tensor_proto
    "supported type." % (type(values), values))
TypeError: Failed to convert object of type <class 'tensorflow.python.framework.sparse_tensor.SparseTensor'> to Tensor. Contents: SparseTensor(indices=Tensor("the_labels/indices:0", shape=(?, 2), dtype=int64), values=Tensor("the_labels/values:0", shape=(?,), dtype=int32), dense_shape=Tensor("the_labels/shape:0", shape=(2,), dtype=int64)). Consider casting elements to a supported type.