class_docstr: Computes example count.
class_docstr_tok: ["Computes","example","count","."]
code: def extract_output(
      self, accumulator: float
  ) -> Dict[metric_types.MetricKey, float]:
      return {k: accumulator for k in self._keys}
  
file_path: model-analysis/tensorflow_model_analysis/metrics/example_count.py
imports: from typing import Optional, Dict, Iterable, List
  import apache_beam
  import numpy
  from tensorflow_model_analysis import constants
  from tensorflow_model_analysis.metrics import metric_types
  from tensorflow_model_analysis.utils import util
label_desc: Use image node_id 5 for calling the _ExampleCountCombiner obj's underlying member method code with example usage: obj.extract_output(accumulator) and returns: unknown