code: def test_contribution_bounding_doesnt_drop_contributions(self):
      # Arrange.
      # input has format (privacy_id, partition_key, (count, sum,
      # num_partitions_contributed)).
      input = [
          ("pid1", "pk1", (1, 2, 3)),
          ("pid2", "pk2", (2, 3, 4)),
          ("pid3", "pk1", (10, 11, 12)),
          ("pid3", "pk3", (100, 101, 102)),
      ]
      bounder = contribution_bounders.NoOpContributionBounder()
  
      # Act.
      bound_result = list(
          bounder.bound_contributions(
              input,
              params=None,
              backend=pipeline_dp.LocalBackend(),
              report_generator=None,
              aggregate_fn=count_aggregate_fn,
          )
      )
  
      # Assert.
      expected_result = [
          (("pid1", "pk1"), 1),
          (("pid2", "pk2"), 2),
          (("pid3", "pk1"), 10),
          (("pid3", "pk3"), 100),
      ]
      self.assertSequenceEqual(set(expected_result), set(bound_result))
  
file_path: pipelinedp/analysis/tests/contribution_bounders_test.py
imports: import collections
  from absl.testing import absltest
  from absl.testing import parameterized
  import pipeline_dp
  import analysis.contribution_bounders
label_desc: Use image node_id 1 for calling the SamplingL0LinfContributionBounderTest obj's underlying member method code with example usage: obj.test_contribution_bounding_doesnt_drop_contributions() without return types