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source: trunk/sources/HeuristicLab.Algorithms.EvolutionStrategy/3.3/EvolutionStrategyMainLoop.cs @ 3326

Last change on this file since 3326 was 3193, checked in by swagner, 15 years ago

Unified *SequentialSubScopesProcessor and *ParallelSubScopesProcessor (#943).
File size: 44.9 KB
RevLine 
[3130]1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2010 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using HeuristicLab.Analysis;
23using HeuristicLab.Core;
24using HeuristicLab.Data;
25using HeuristicLab.Operators;
26using HeuristicLab.Optimization.Operators;
27using HeuristicLab.Parameters;
28using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
29using HeuristicLab.Selection;
30using HeuristicLab.Encodings.RealVectorEncoding;
31
32namespace HeuristicLab.Algorithms.EvolutionStrategy {
33  /// <summary>
34  /// An operator which represents the main loop of an evolution strategy (EvolutionStrategy).
35  /// </summary>
36  [Item("EvolutionStrategyMainLoop", "An operator which represents the main loop of an evolution strategy (EvolutionStrategy).")]
37  [StorableClass]
38  public sealed class EvolutionStrategyMainLoop : AlgorithmOperator {
39    #region Parameter properties
40    public ValueLookupParameter<IRandom> RandomParameter {
41      get { return (ValueLookupParameter<IRandom>)Parameters["Random"]; }
42    }
43    public ValueLookupParameter<BoolValue> MaximizationParameter {
44      get { return (ValueLookupParameter<BoolValue>)Parameters["Maximization"]; }
45    }
46    public SubScopesLookupParameter<DoubleValue> QualityParameter {
47      get { return (SubScopesLookupParameter<DoubleValue>)Parameters["Quality"]; }
48    }
49    public ValueLookupParameter<DoubleValue> BestKnownQualityParameter {
50      get { return (ValueLookupParameter<DoubleValue>)Parameters["BestKnownQuality"]; }
51    }
52    public ValueLookupParameter<IntValue> PopulationSizeParameter {
53      get { return (ValueLookupParameter<IntValue>)Parameters["PopulationSize"]; }
54    }
55    public ValueLookupParameter<IntValue> ParentsPerChildParameter {
56      get { return (ValueLookupParameter<IntValue>)Parameters["ParentsPerChild"]; }
57    }
58    public ValueLookupParameter<IntValue> ChildrenParameter {
59      get { return (ValueLookupParameter<IntValue>)Parameters["Children"]; }
60    }
61    public ValueLookupParameter<RealVector> StrategyVectorParameter {
62      get { return (ValueLookupParameter<RealVector>)Parameters["StrategyVector"]; }
63    }
64    public ValueLookupParameter<DoubleMatrix> StrategyVectorBoundsParameter {
65      get { return (ValueLookupParameter<DoubleMatrix>)Parameters["StrategyVectorBounds"]; }
66    }
67    public ValueLookupParameter<DoubleValue> GeneralLearningRateParameter {
68      get { return (ValueLookupParameter<DoubleValue>)Parameters["GeneralLearningRate"]; }
69    }
70    public ValueLookupParameter<DoubleValue> LearningRateParameter {
71      get { return (ValueLookupParameter<DoubleValue>)Parameters["LearningRate"]; }
72    }
73    public ValueLookupParameter<BoolValue> PlusSelectionParameter {
74      get { return (ValueLookupParameter<BoolValue>)Parameters["PlusSelection"]; }
75    }
76    public ValueLookupParameter<IntValue> MaximumGenerationsParameter {
77      get { return (ValueLookupParameter<IntValue>)Parameters["MaximumGenerations"]; }
78    }
79    public ValueLookupParameter<IOperator> MutatorParameter {
80      get { return (ValueLookupParameter<IOperator>)Parameters["Mutator"]; }
81    }
82    public ValueLookupParameter<IOperator> RecombinatorParameter {
83      get { return (ValueLookupParameter<IOperator>)Parameters["Recombinator"]; }
84    }
85    public ValueLookupParameter<IOperator> EvaluatorParameter {
86      get { return (ValueLookupParameter<IOperator>)Parameters["Evaluator"]; }
87    }
88    public ValueLookupParameter<VariableCollection> ResultsParameter {
89      get { return (ValueLookupParameter<VariableCollection>)Parameters["Results"]; }
90    }
91    public ValueLookupParameter<IOperator> VisualizerParameter {
92      get { return (ValueLookupParameter<IOperator>)Parameters["Visualizer"]; }
93    }
94    public LookupParameter<IItem> VisualizationParameter {
95      get { return (LookupParameter<IItem>)Parameters["Visualization"]; }
96    }
97    private ScopeParameter CurrentScopeParameter {
98      get { return (ScopeParameter)Parameters["CurrentScope"]; }
99    }
100
101    public IScope CurrentScope {
102      get { return CurrentScopeParameter.ActualValue; }
103    }
104    #endregion
105
106    [StorableConstructor]
107    private EvolutionStrategyMainLoop(bool deserializing) : base() { }
108    public EvolutionStrategyMainLoop()
109      : base() {
110      Initialize();
111    }
112
113    private void Initialize() {
114      #region Create parameters
115      Parameters.Add(new ValueLookupParameter<IRandom>("Random", "A pseudo random number generator."));
116      Parameters.Add(new ValueLookupParameter<BoolValue>("Maximization", "True if the problem is a maximization problem, otherwise false."));
117      Parameters.Add(new SubScopesLookupParameter<DoubleValue>("Quality", "The value which represents the quality of a solution."));
118      Parameters.Add(new ValueLookupParameter<DoubleValue>("BestKnownQuality", "The best known quality value found so far."));
119      Parameters.Add(new ValueLookupParameter<IntValue>("PopulationSize", "µ (mu) - the size of the population."));
120      Parameters.Add(new ValueLookupParameter<IntValue>("ParentsPerChild", "ρ (rho) - how many parents should be recombined."));
121      Parameters.Add(new ValueLookupParameter<IntValue>("Children", "λ (lambda) - the size of the offspring population."));
122      Parameters.Add(new ValueLookupParameter<IntValue>("MaximumGenerations", "The maximum number of generations which should be processed."));
123      Parameters.Add(new ValueLookupParameter<RealVector>("StrategyVector", "The strategy vector."));
124      Parameters.Add(new LookupParameter<DoubleMatrix>("StrategyVectorBounds", "2 column matrix with one row for each dimension specifying upper and lower bound for the strategy vector. If there are less rows than dimensions, the strategy vector will be read in a cycle."));
125      Parameters.Add(new ValueLookupParameter<DoubleValue>("GeneralLearningRate", "τ0 (tau0) - the factor with which adjustments in the strategy vector is dampened over all dimensions. Recommendation is to use 1/Sqrt(2*ProblemDimension)."));
126      Parameters.Add(new ValueLookupParameter<DoubleValue>("LearningRate", "τ (tau) - the factor with which adjustments in the strategy vector are dampened in a single dimension. Recommendation is to use 1/Sqrt(2*Sqrt(ProblemDimension))."));
127      Parameters.Add(new ValueLookupParameter<BoolValue>("PlusSelection", "True for plus selection (elitist population), false for comma selection (non-elitist population)."));
128      Parameters.Add(new ValueLookupParameter<IOperator>("Mutator", "The operator used to mutate solutions."));
129      Parameters.Add(new ValueLookupParameter<IOperator>("Recombinator", "The operator used to cross solutions."));
130      Parameters.Add(new ValueLookupParameter<IOperator>("Evaluator", "The operator used to evaluate solutions."));
131      Parameters.Add(new ValueLookupParameter<VariableCollection>("Results", "The variable collection where results should be stored."));
132      Parameters.Add(new ValueLookupParameter<IOperator>("Visualizer", "The operator used to visualize solutions."));
133      Parameters.Add(new LookupParameter<IItem>("Visualization", "The item which represents the visualization of solutions."));
134      Parameters.Add(new ScopeParameter("CurrentScope", "The current scope which represents a population of solutions on which the EvolutionStrategy should be applied."));
135      #endregion
136
137      #region Create operators
138      VariableCreator variableCreator = new VariableCreator();
139      BestQualityMemorizer bestQualityMemorizer1 = new BestQualityMemorizer();
140      BestQualityMemorizer bestQualityMemorizer2 = new BestQualityMemorizer();
141      BestAverageWorstQualityCalculator bestAverageWorstQualityCalculator1 = new BestAverageWorstQualityCalculator();
142      DataTableValuesCollector dataTableValuesCollector1 = new DataTableValuesCollector();
143      QualityDifferenceCalculator qualityDifferenceCalculator1 = new QualityDifferenceCalculator();
144      Placeholder visualizer1 = new Placeholder();
145      ResultsCollector resultsCollector = new ResultsCollector();
146      WithoutRepeatingBatchedRandomSelector selector = new WithoutRepeatingBatchedRandomSelector();
147      SubScopesProcessor subScopesProcessor1 = new SubScopesProcessor();
148      Comparator useRecombinationComparator = new Comparator();
149      ConditionalBranch useRecombinationBranch = new ConditionalBranch();
150      ChildrenCreator childrenCreator = new ChildrenCreator();
151      UniformSubScopesProcessor uniformSubScopesProcessor1 = new UniformSubScopesProcessor();
152      Placeholder recombinator = new Placeholder();
153      StrategyVectorManipulator strategyMutator1 = new StrategyVectorManipulator();
154      Placeholder mutator1 = new Placeholder();
155      Placeholder evaluator1 = new Placeholder();
156      SubScopesRemover subScopesRemover = new SubScopesRemover();
157      UniformSubScopesProcessor uniformSubScopesProcessor2 = new UniformSubScopesProcessor();
158      StrategyVectorManipulator strategyMutator2 = new StrategyVectorManipulator();
159      Placeholder mutator2 = new Placeholder();
160      Placeholder evaluator2 = new Placeholder();
161      ConditionalBranch plusOrCommaReplacementBranch = new ConditionalBranch();
162      MergingReducer plusReplacement = new MergingReducer();
163      RightReducer commaReplacement = new RightReducer();
164      BestSelector bestSelector = new BestSelector();
165      RightReducer rightReducer = new RightReducer();
166      IntCounter intCounter = new IntCounter();
167      Comparator comparator = new Comparator();
168      BestQualityMemorizer bestQualityMemorizer3 = new BestQualityMemorizer();
169      BestQualityMemorizer bestQualityMemorizer4 = new BestQualityMemorizer();
170      BestAverageWorstQualityCalculator bestAverageWorstQualityCalculator2 = new BestAverageWorstQualityCalculator();
171      DataTableValuesCollector dataTableValuesCollector2 = new DataTableValuesCollector();
172      QualityDifferenceCalculator qualityDifferenceCalculator2 = new QualityDifferenceCalculator();
173      Placeholder visualizer2 = new Placeholder();
174      ConditionalBranch conditionalBranch = new ConditionalBranch();
175
176      variableCreator.CollectedValues.Add(new ValueParameter<IntValue>("Generations", new IntValue(0)));
177
178      bestQualityMemorizer1.BestQualityParameter.ActualName = "BestQuality";
179      bestQualityMemorizer1.MaximizationParameter.ActualName = MaximizationParameter.Name;
180      bestQualityMemorizer1.QualityParameter.ActualName = QualityParameter.Name;
181
182      bestQualityMemorizer2.BestQualityParameter.ActualName = BestKnownQualityParameter.Name;
183      bestQualityMemorizer2.MaximizationParameter.ActualName = MaximizationParameter.Name;
184      bestQualityMemorizer2.QualityParameter.ActualName = QualityParameter.Name;
185
186      bestAverageWorstQualityCalculator1.AverageQualityParameter.ActualName = "CurrentAverageQuality";
187      bestAverageWorstQualityCalculator1.BestQualityParameter.ActualName = "CurrentBestQuality";
188      bestAverageWorstQualityCalculator1.MaximizationParameter.ActualName = MaximizationParameter.Name;
189      bestAverageWorstQualityCalculator1.QualityParameter.ActualName = QualityParameter.Name;
190      bestAverageWorstQualityCalculator1.WorstQualityParameter.ActualName = "CurrentWorstQuality";
191
192      dataTableValuesCollector1.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Best Quality", null, "CurrentBestQuality"));
193      dataTableValuesCollector1.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Average Quality", null, "CurrentAverageQuality"));
194      dataTableValuesCollector1.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Worst Quality", null, "CurrentWorstQuality"));
195      dataTableValuesCollector1.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Quality", null, "BestQuality"));
196      dataTableValuesCollector1.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Known Quality", null, BestKnownQualityParameter.Name));
197      dataTableValuesCollector1.DataTableParameter.ActualName = "Qualities";
198
199      qualityDifferenceCalculator1.AbsoluteDifferenceParameter.ActualName = "AbsoluteDifferenceBestKnownToBest";
200      qualityDifferenceCalculator1.FirstQualityParameter.ActualName = BestKnownQualityParameter.Name;
201      qualityDifferenceCalculator1.RelativeDifferenceParameter.ActualName = "RelativeDifferenceBestKnownToBest";
202      qualityDifferenceCalculator1.SecondQualityParameter.ActualName = "BestQuality";
203
204      visualizer1.Name = "Visualizer (placeholder)";
205      visualizer1.OperatorParameter.ActualName = VisualizerParameter.Name;
206
207      resultsCollector.CollectedValues.Add(new LookupParameter<IntValue>("Generations"));
208      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Best Quality", null, "CurrentBestQuality"));
209      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Average Quality", null, "CurrentAverageQuality"));
210      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Worst Quality", null, "CurrentWorstQuality"));
211      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Quality", null, "BestQuality"));
212      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Known Quality", null, BestKnownQualityParameter.Name));
213      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Absolute Difference of Best Known Quality to Best Quality", null, "AbsoluteDifferenceBestKnownToBest"));
214      resultsCollector.CollectedValues.Add(new LookupParameter<DoubleValue>("Relative Difference of Best Known Quality to Best Quality", null, "RelativeDifferenceBestKnownToBest"));
215      resultsCollector.CollectedValues.Add(new LookupParameter<IItem>("Solution Visualization", null, VisualizationParameter.Name));
216      resultsCollector.CollectedValues.Add(new LookupParameter<DataTable>("Qualities"));
217      resultsCollector.ResultsParameter.ActualName = ResultsParameter.Name;
218
219      selector.Name = "ES Random Selector";
220      selector.ParentsPerChildParameter.ActualName = ParentsPerChildParameter.Name;
221      selector.ChildrenParameter.ActualName = ChildrenParameter.Name;
222
223      useRecombinationComparator.Name = "ParentsPerChild > 1";
224      useRecombinationComparator.LeftSideParameter.ActualName = ParentsPerChildParameter.Name;
225      useRecombinationComparator.RightSideParameter.Value = new IntValue(1);
226      useRecombinationComparator.Comparison = new Comparison(ComparisonType.Greater);
227      useRecombinationComparator.ResultParameter.ActualName = "UseRecombination";
228
229      useRecombinationBranch.Name = "Use Recombination?";
230      useRecombinationBranch.ConditionParameter.ActualName = "UseRecombination";
231
232      childrenCreator.ParentsPerChildParameter.ActualName = ParentsPerChildParameter.Name;
233
234      recombinator.Name = "Recombinator (placeholder)";
235      recombinator.OperatorParameter.ActualName = RecombinatorParameter.Name;
236
237      strategyMutator1.StrategyVectorParameter.ActualName = StrategyVectorParameter.Name;
238      strategyMutator1.GeneralLearningRateParameter.ActualName = GeneralLearningRateParameter.Name;
239      strategyMutator1.LearningRateParameter.ActualName = LearningRateParameter.Name;
240      strategyMutator1.RandomParameter.ActualName = RandomParameter.Name;
241
242      mutator1.Name = "Mutator (placeholder)";
243      mutator1.OperatorParameter.ActualName = MutatorParameter.Name;
244
245      evaluator1.Name = "Evaluator (placeholder)";
246      evaluator1.OperatorParameter.ActualName = EvaluatorParameter.Name;
247
248      subScopesRemover.RemoveAllSubScopes = true;
249
250      strategyMutator2.StrategyVectorParameter.ActualName = StrategyVectorParameter.Name;
251      strategyMutator2.GeneralLearningRateParameter.ActualName = GeneralLearningRateParameter.Name;
252      strategyMutator2.LearningRateParameter.ActualName = LearningRateParameter.Name;
253      strategyMutator2.RandomParameter.ActualName = RandomParameter.Name;
254
255      mutator2.Name = "Mutator (placeholder)";
256      mutator2.OperatorParameter.ActualName = MutatorParameter.Name;
257
258      evaluator2.Name = "Evaluator (placeholder)";
259      evaluator2.OperatorParameter.ActualName = EvaluatorParameter.Name;
260
261      plusOrCommaReplacementBranch.ConditionParameter.ActualName = PlusSelectionParameter.Name;
262
263      bestSelector.CopySelected = new BoolValue(false);
264      bestSelector.MaximizationParameter.ActualName = MaximizationParameter.Name;
265      bestSelector.NumberOfSelectedSubScopesParameter.ActualName = PopulationSizeParameter.Name;
266      bestSelector.QualityParameter.ActualName = QualityParameter.Name;
267
268      intCounter.Increment = new IntValue(1);
269      intCounter.ValueParameter.ActualName = "Generations";
270
271      comparator.Comparison = new Comparison(ComparisonType.GreaterOrEqual);
272      comparator.LeftSideParameter.ActualName = "Generations";
273      comparator.ResultParameter.ActualName = "Terminate";
274      comparator.RightSideParameter.ActualName = MaximumGenerationsParameter.Name;
275
276      bestQualityMemorizer3.BestQualityParameter.ActualName = "BestQuality";
277      bestQualityMemorizer3.MaximizationParameter.ActualName = MaximizationParameter.Name;
278      bestQualityMemorizer3.QualityParameter.ActualName = QualityParameter.Name;
279
280      bestQualityMemorizer4.BestQualityParameter.ActualName = BestKnownQualityParameter.Name;
281      bestQualityMemorizer4.MaximizationParameter.ActualName = MaximizationParameter.Name;
282      bestQualityMemorizer4.QualityParameter.ActualName = QualityParameter.Name;
283
284      bestAverageWorstQualityCalculator2.AverageQualityParameter.ActualName = "CurrentAverageQuality";
285      bestAverageWorstQualityCalculator2.BestQualityParameter.ActualName = "CurrentBestQuality";
286      bestAverageWorstQualityCalculator2.MaximizationParameter.ActualName = MaximizationParameter.Name;
287      bestAverageWorstQualityCalculator2.QualityParameter.ActualName = QualityParameter.Name;
288      bestAverageWorstQualityCalculator2.WorstQualityParameter.ActualName = "CurrentWorstQuality";
289
290      dataTableValuesCollector2.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Best Quality", null, "CurrentBestQuality"));
291      dataTableValuesCollector2.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Average Quality", null, "CurrentAverageQuality"));
292      dataTableValuesCollector2.CollectedValues.Add(new LookupParameter<DoubleValue>("Current Worst Quality", null, "CurrentWorstQuality"));
293      dataTableValuesCollector2.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Quality", null, "BestQuality"));
294      dataTableValuesCollector2.CollectedValues.Add(new LookupParameter<DoubleValue>("Best Known Quality", null, BestKnownQualityParameter.Name));
295      dataTableValuesCollector2.DataTableParameter.ActualName = "Qualities";
296
297      qualityDifferenceCalculator2.AbsoluteDifferenceParameter.ActualName = "AbsoluteDifferenceBestKnownToBest";
298      qualityDifferenceCalculator2.FirstQualityParameter.ActualName = BestKnownQualityParameter.Name;
299      qualityDifferenceCalculator2.RelativeDifferenceParameter.ActualName = "RelativeDifferenceBestKnownToBest";
300      qualityDifferenceCalculator2.SecondQualityParameter.ActualName = "BestQuality";
301
302      visualizer2.Name = "Visualizer (placeholder)";
303      visualizer2.OperatorParameter.ActualName = VisualizerParameter.Name;
304
305      conditionalBranch.ConditionParameter.ActualName = "Terminate";
306      #endregion
307
308      #region Create operator graph
309      OperatorGraph.InitialOperator = variableCreator;
310      variableCreator.Successor = bestQualityMemorizer1;
311      bestQualityMemorizer1.Successor = bestQualityMemorizer2;
312      bestQualityMemorizer2.Successor = bestAverageWorstQualityCalculator1;
313      bestAverageWorstQualityCalculator1.Successor = dataTableValuesCollector1;
314      dataTableValuesCollector1.Successor = qualityDifferenceCalculator1;
315      qualityDifferenceCalculator1.Successor = visualizer1;
316      visualizer1.Successor = resultsCollector;
317      resultsCollector.Successor = selector;
318      selector.Successor = subScopesProcessor1;
319      subScopesProcessor1.Operators.Add(new EmptyOperator());
320      subScopesProcessor1.Operators.Add(useRecombinationComparator);
321      subScopesProcessor1.Successor = plusOrCommaReplacementBranch;
322      useRecombinationComparator.Successor = useRecombinationBranch;
323      useRecombinationBranch.TrueBranch = childrenCreator;
324      useRecombinationBranch.FalseBranch = uniformSubScopesProcessor2;
325      useRecombinationBranch.Successor = null;
326      childrenCreator.Successor = uniformSubScopesProcessor1;
327      uniformSubScopesProcessor1.Operator = recombinator;
328      uniformSubScopesProcessor1.Successor = null;
329      recombinator.Successor = strategyMutator1;
330      strategyMutator1.Successor = mutator1;
331      mutator1.Successor = evaluator1;
332      evaluator1.Successor = subScopesRemover;
333      subScopesRemover.Successor = null;
334      uniformSubScopesProcessor2.Operator = strategyMutator2;
335      uniformSubScopesProcessor2.Successor = null;
336      strategyMutator2.Successor = mutator2;
337      mutator2.Successor = evaluator2;
338      plusOrCommaReplacementBranch.TrueBranch = plusReplacement;
339      plusOrCommaReplacementBranch.FalseBranch = commaReplacement;
340      plusOrCommaReplacementBranch.Successor = bestSelector;
341      bestSelector.Successor = rightReducer;
342      rightReducer.Successor = intCounter;
343      intCounter.Successor = comparator;
344      comparator.Successor = bestQualityMemorizer3;
345      bestQualityMemorizer3.Successor = bestQualityMemorizer4;
346      bestQualityMemorizer4.Successor = bestAverageWorstQualityCalculator2;
347      bestAverageWorstQualityCalculator2.Successor = dataTableValuesCollector2;
348      dataTableValuesCollector2.Successor = qualityDifferenceCalculator2;
349      qualityDifferenceCalculator2.Successor = visualizer2;
350      visualizer2.Successor = conditionalBranch;
351      conditionalBranch.FalseBranch = selector;
352      conditionalBranch.TrueBranch = null;
353      conditionalBranch.Successor = null;
354      #endregion
355    }
356  }
357}
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