code: def test_create_report_partition_size_is_used_as_weight_wo_mocks(
      self,
  ):
      combiner = self._create_combiner(
          weight_fn=cross_partition_combiners.partition_size_weight_fn
      )
      per_partition_metrics = metrics.PerPartitionMetrics(
          partition_selection_probability_to_keep=0.2,
          raw_statistics=metrics.RawStatistics(
              privacy_id_count=3, count=9
          ),
          metric_errors=[_get_default_sum_metrics(sum=5.0)],
      )
      _, _, weight = combiner.create_accumulator(per_partition_metrics)
      self.assertEqual(weight, 5.0)
  
imports: from absl.testing import absltest
  from absl.testing import parameterized
  import dataclasses
  import math
  from unittest import mock
  from unittest.mock import patch
  from analysis import metrics
  from analysis import cross_partition_combiners
  import pipeline_dp
label_desc: Use image node_id 3 for calling the CrossPartitionCombiner obj's underlying member method code with example usage: obj.test_create_report_partition_size_is_used_as_weight_wo_mocks() without return types