class_docstr: A `Dataset` that concatenates its input with given dataset.
code: def element_spec(self):
      return self._structure
  
file_path: tensorflow-upstream/tensorflow/python/data/ops/concatenate_op.py
imports: from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.ops import gen_dataset_ops
  from tensorflow.python.util import nest
label_desc: Use image node_id 3 for calling the _ConcatenateDataset obj's underlying member method code with example usage: obj.element_spec() and returns: self