class_docstr: A visitor that inspects the graph and looks for dataset keys in use.
code: def __init__(self, required_dataset_keys_output):
      self._required_dataset_keys = required_dataset_keys_output
  
imports: import collections
  import dataclasses
  import hashlib
  from typing import Collection, Dict, Mapping, Optional, Tuple
  from typing import OrderedDict
  import tensorflow
  from tensorflow_transform import analyzer_nodes
  from tensorflow_transform import common_types
  from tensorflow_transform import graph_tools
  from tensorflow_transform import impl_helper
  from tensorflow_transform import nodes
  from tensorflow_transform import tf2_utils
  from tensorflow_transform import tf_utils
  from tensorflow_transform.beam import analyzer_cache
  from tensorflow_transform.beam import beam_nodes
  from tensorflow_transform.beam import combiner_packing_util
label_desc: Use image node_id 1 to create a new _InspectVisitor object from inherited base classes: nodes with example: obj = _InspectVisitor(required_dataset_keys_output)