code: def test_sum_metrics_to_data_dropped_sum(self):
      input = metrics.SumMetrics(
          aggregation=pipeline_dp.Metrics.SUM,
          sum=12,
          clipping_to_min_error=3.0,
          clipping_to_max_error=-5.0,
          expected_l0_bounding_error=-2.0,
          std_l0_bounding_error=3.0,
          std_noise=4.0,
          noise_kind=pipeline_dp.NoiseKind.LAPLACE,
      )
  
      output = cross_partition_combiners._sum_metrics_to_data_dropped(
          input,
          partition_keep_probability=0.5,
          dp_metric=pipeline_dp.Metrics.SUM,
      )
  
      self.assertEqual(
          output,
          metrics.DataDropInfo(
              l0=2.0, linf=8.0, partition_selection=1.0
          ),
      )
  
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 7 for calling the PerPartitionToCrossPartitionMetrics obj's underlying member method code with example usage: obj.test_sum_metrics_to_data_dropped_sum() without return types