code: def _TrackDistinctSliceKeys(  # pylint: disable=invalid-name
      slice_keys_and_values: beam.pvalue.PCollection,
  ) -> beam.pvalue.PCollection:
      """Gathers slice key telemetry post slicing."""
  
      def increment_counter(element):  # pylint: disable=invalid-name
          num_distinct_slice_keys = beam.metrics.Metrics.counter(
              constants.METRICS_NAMESPACE, "num_distinct_slice_keys"
          )
          num_distinct_slice_keys.inc(element)
          return element
  
      return (
          slice_keys_and_values
          | "ExtractSliceKeys" >> beam.Keys()
          | "RemoveDuplicates" >> beam.Distinct()
          | "Size" >> beam.combiners.Count.Globally()
          | "IncrementCounter" >> beam.Map(increment_counter)
      )
  
imports: import itertools
  from typing import Any, Callable, Dict, Generator, Iterable, List, NamedTuple, Optional, Tuple, Union
  import apache_beam
  import numpy
  import tensorflow
  from tensorflow_model_analysis import constants
  from tensorflow_model_analysis.api import types
  from tensorflow_model_analysis.proto import config_pb2
  from tensorflow_model_analysis.proto import metrics_for_slice_pb2
  from tensorflow_model_analysis.slicer import slice_accessor
label_desc: Use image node_id 14 for calling a global function with example usage: _TrackDistinctSliceKeys(slice_keys_and_values) and returns: unknown, element