code: def test_mean_calls_aggregate_with_params(self, mock_aggregate):
      runner = fn_api_runner.FnApiRunner()
      with beam.Pipeline(runner=runner) as pipeline:
          # Arrange
          pcol = pipeline | "Create produce" >> beam.Create(
              [1, 2, 3, 4, 5, 6]
          )
          budget_accountant = budget_accounting.NaiveBudgetAccountant(
              total_epsilon=1, total_delta=0.01
          )
          private_collection = (
              pcol
              | "Create private collection"
              >> private_beam.MakePrivate(
                  budget_accountant=budget_accountant,
                  privacy_id_extractor=PrivateBeamTest.privacy_id_extractor,
              )
          )
  
          mean_params = aggregate_params.MeanParams(
              noise_kind=pipeline_dp.NoiseKind.GAUSSIAN,
              max_partitions_contributed=2,
              max_contributions_per_partition=3,
              min_value=1,
              max_value=5,
              budget_weight=1,
              partition_extractor=lambda x: f"pk:{x // 10}",
              value_extractor=lambda x: x,
          )
  
          # Act
          transformer = private_beam.Mean(
              mean_params=mean_params, public_partitions=[]
          )
          private_collection | transformer
  
          # Assert
          self.assertEqual(
              transformer._budget_accountant, budget_accountant
          )
          mock_aggregate.assert_called_once()
  
          args = mock_aggregate.call_args[0]
  
          params = pipeline_dp.AggregateParams(
              noise_kind=pipeline_dp.NoiseKind.GAUSSIAN,
              metrics=[pipeline_dp.Metrics.MEAN],
              max_partitions_contributed=mean_params.max_partitions_contributed,
              max_contributions_per_partition=mean_params.max_contributions_per_partition,
              min_value=mean_params.min_value,
              max_value=mean_params.max_value,
          )
          self.assertEqual(params, args[1])
  
imports: import unittest
  import apache_beam
  from apache_beam.runners.portability import fn_api_runner
  from apache_beam import pvalue
  from unittest.mock import patch
  import apache_beam.testing.util
  from apache_beam.testing.test_pipeline import TestPipeline
  import pipeline_dp
  from pipeline_dp import private_beam
  from pipeline_dp import aggregate_params, budget_accounting
label_desc: Use image node_id 11 for calling the PrivateBeamTest obj's underlying member method code with example usage: obj.test_mean_calls_aggregate_with_params(mock_aggregate) without return types