class_docstr: Approximately computes unique values on the PCollection.
code: def add_input(
      self,
      accumulator: sketches.MisraGriesSketch,
      next_input: Tuple[np.ndarray, np.ndarray],
  ) -> sketches.MisraGriesSketch:
      items, weights = next_input
      if items.size:
          accumulator.AddValues(
              pa.array(items), pa.array(weights, pa.float32())
          )
      return accumulator
  
imports: from typing import Any, Collection, List, Optional, Tuple, Union, Iterable, Sequence
  import numpy
  import pyarrow
  import tensorflow
  from tensorflow_transform import analyzer_nodes
  from tensorflow_transform import analyzers
  from tensorflow_transform import common
  from tensorflow_transform import common_types
  from tensorflow_transform import nodes
  from tensorflow_transform import tf_utils
  from tfx_bsl import sketches
  from tfx_bsl.types import tfx_namedtuple
  from typing_extensions import Protocol
label_desc: Use image node_id 3 for calling the _VocabularyCombiner obj's underlying member method code with example usage: obj.add_input(accumulator, next_input) and returns: accumulator