code: def create_dp_engine_default(
      self,
      accountant: NaiveBudgetAccountant = None,
      backend: PipelineBackend = None,
  ):
      if not accountant:
          accountant = NaiveBudgetAccountant(
              total_epsilon=1, total_delta=1e-10
          )
      if not backend:
          backend = pipeline_dp.LocalBackend()
      dp_engine = pipeline_dp.DPEngine(accountant, backend)
      aggregator_params = pipeline_dp.AggregateParams(
          noise_kind=pipeline_dp.NoiseKind.LAPLACE,
          metrics=[],
          max_partitions_contributed=1,
          max_contributions_per_partition=1,
      )
      dp_engine._report_generators.append(
          ReportGenerator(aggregator_params, method_name="test")
      )
      dp_engine._add_report_stage("DP Engine Test")
      return dp_engine
  
imports: import sys
  import unittest
  from typing import List, Optional, Tuple
  from unittest.mock import patch
  import numpy
  import apache_beam
  import apache_beam.testing.test_pipeline
  import apache_beam.testing.util
  import pydp.algorithms.partition_selection
  from absl.testing import absltest
  from absl.testing import parameterized
  import pipeline_dp
  from pipeline_dp import aggregate_params
  from pipeline_dp import budget_accounting
  from pipeline_dp import dp_computations
  from pipeline_dp.budget_accounting import NaiveBudgetAccountant
  from pipeline_dp.pipeline_backend import PipelineBackend
  from pipeline_dp.pipeline_functions import collect_to_container
  from pipeline_dp.report_generator import ReportGenerator
label_desc: Use image node_id 30 for calling the DpEngineTest obj's underlying member method code with example usage: obj.create_dp_engine_default(accountant, backend) and returns: dp_engine