class_docstr: DP sum combiner.
  
  It is just for demonstration how custom combiners API work.
class_docstr_tok: ["DP","sum","combiner",".","It","is","just","for","demonstration","how","custom","combiners","API","work","."]
docstr: Merges the accumulators and returns accumulator.
docstr_tok: ["Merges","the","accumulators","and","returns","accumulator","."]
code: def merge_accumulators(self, count1, count2):
      """Merges the accumulators and returns accumulator."""
      return count1 + count2
  
imports: from absl import app
  from absl import flags
  from apache_beam.runners.portability import fn_api_runner
  import pyspark
  from examples.movie_view_ratings.common_utils import *
  import pipeline_dp
  import numpy
label_desc: Use image node_id 2 for calling the CountCombiner obj's underlying member method code with example usage: obj.merge_accumulators(count1, count2) and returns: unknown