class_docstr: Approximately computes unique values on the PCollection.
code: def merge_accumulators(
      self, accumulators: Iterable[sketches.MisraGriesSketch]
  ) -> sketches.MisraGriesSketch:
      # Make sure that `accumulators` is an iterator (so that the position is
      # remembered).
      accumulators = iter(accumulators)
      result = next(accumulators)
      for accumulator in accumulators:
          result.Merge(accumulator)
      return result
  
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 4 for calling the _VocabularyCombiner obj's underlying member method code with example usage: obj.merge_accumulators(accumulators) and returns: result