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source: branches/HeuristicLab.EvolutionTracking/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/SymbolicDataAnalysisProblem.cs @ 10755

Last change on this file since 10755 was 10462, checked in by bburlacu, 11 years ago

#1772: Fixed bug in configuration of the tracking operators, fixed null reference exception when trying to access fragments in SymbolicDataAnalysisGenealogyGraphView
File size: 22.0 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2013 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 System;
23using System.Drawing;
24using System.Linq;
25using HeuristicLab.Common;
26using HeuristicLab.Common.Resources;
27using HeuristicLab.Core;
28using HeuristicLab.Data;
29using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
30using HeuristicLab.EvolutionTracking;
31using HeuristicLab.Optimization;
32using HeuristicLab.Parameters;
33using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
34using HeuristicLab.PluginInfrastructure;
35using HeuristicLab.Problems.DataAnalysis.Symbolic.Analyzers;
36using HeuristicLab.Problems.Instances;
37
38
39namespace HeuristicLab.Problems.DataAnalysis.Symbolic {
40  [StorableClass]
41  public abstract class SymbolicDataAnalysisProblem<T, U, V> : HeuristicOptimizationProblem<U, V>, IDataAnalysisProblem<T>, ISymbolicDataAnalysisProblem, IStorableContent,
42    IProblemInstanceConsumer<T>, IProblemInstanceExporter<T>
43    where T : class, IDataAnalysisProblemData
44    where U : class, ISymbolicDataAnalysisEvaluator<T>
45    where V : class, ISymbolicDataAnalysisSolutionCreator {
46
47    #region parameter names & descriptions
48    private const string ProblemDataParameterName = "ProblemData";
49    private const string SymbolicExpressionTreeGrammarParameterName = "SymbolicExpressionTreeGrammar";
50    private const string SymbolicExpressionTreeInterpreterParameterName = "SymbolicExpressionTreeInterpreter";
51    private const string MaximumSymbolicExpressionTreeDepthParameterName = "MaximumSymbolicExpressionTreeDepth";
52    private const string MaximumSymbolicExpressionTreeLengthParameterName = "MaximumSymbolicExpressionTreeLength";
53    private const string MaximumFunctionDefinitionsParameterName = "MaximumFunctionDefinitions";
54    private const string MaximumFunctionArgumentsParameterName = "MaximumFunctionArguments";
55    private const string RelativeNumberOfEvaluatedSamplesParameterName = "RelativeNumberOfEvaluatedSamples";
56    private const string FitnessCalculationPartitionParameterName = "FitnessCalculationPartition";
57    private const string ValidationPartitionParameterName = "ValidationPartition";
58    private const string ApplyLinearScalingParameterName = "ApplyLinearScaling";
59
60    private const string ProblemDataParameterDescription = "";
61    private const string SymbolicExpressionTreeGrammarParameterDescription = "The grammar that should be used for symbolic expression tree.";
62    private const string SymoblicExpressionTreeInterpreterParameterDescription = "The interpreter that should be used to evaluate the symbolic expression tree.";
63    private const string MaximumSymbolicExpressionTreeDepthParameterDescription = "Maximal depth of the symbolic expression. The minimum depth needed for the algorithm is 3 because two levels are reserved for the ProgramRoot and the Start symbol.";
64    private const string MaximumSymbolicExpressionTreeLengthParameterDescription = "Maximal length of the symbolic expression.";
65    private const string MaximumFunctionDefinitionsParameterDescription = "Maximal number of automatically defined functions";
66    private const string MaximumFunctionArgumentsParameterDescription = "Maximal number of arguments of automatically defined functions.";
67    private const string RelativeNumberOfEvaluatedSamplesParameterDescription = "The relative number of samples of the dataset partition, which should be randomly chosen for evaluation.";
68    private const string FitnessCalculationPartitionParameterDescription = "The partition of the problem data training partition, that should be used to calculate the fitness of an individual.";
69    private const string ValidationPartitionParameterDescription = "The partition of the problem data training partition, that should be used to select the best model from (optional).";
70    private const string ApplyLinearScalingParameterDescription = "Flag that indicates if the individual should be linearly scaled before evaluating.";
71    #endregion
72
73    #region parameter properties
74    IParameter IDataAnalysisProblem.ProblemDataParameter {
75      get { return ProblemDataParameter; }
76    }
77    public IValueParameter<T> ProblemDataParameter {
78      get { return (IValueParameter<T>)Parameters[ProblemDataParameterName]; }
79    }
80    public IValueParameter<ISymbolicDataAnalysisGrammar> SymbolicExpressionTreeGrammarParameter {
81      get { return (IValueParameter<ISymbolicDataAnalysisGrammar>)Parameters[SymbolicExpressionTreeGrammarParameterName]; }
82    }
83    public IValueParameter<ISymbolicDataAnalysisExpressionTreeInterpreter> SymbolicExpressionTreeInterpreterParameter {
84      get { return (IValueParameter<ISymbolicDataAnalysisExpressionTreeInterpreter>)Parameters[SymbolicExpressionTreeInterpreterParameterName]; }
85    }
86    public IFixedValueParameter<IntValue> MaximumSymbolicExpressionTreeDepthParameter {
87      get { return (IFixedValueParameter<IntValue>)Parameters[MaximumSymbolicExpressionTreeDepthParameterName]; }
88    }
89    public IFixedValueParameter<IntValue> MaximumSymbolicExpressionTreeLengthParameter {
90      get { return (IFixedValueParameter<IntValue>)Parameters[MaximumSymbolicExpressionTreeLengthParameterName]; }
91    }
92    public IFixedValueParameter<IntValue> MaximumFunctionDefinitionsParameter {
93      get { return (IFixedValueParameter<IntValue>)Parameters[MaximumFunctionDefinitionsParameterName]; }
94    }
95    public IFixedValueParameter<IntValue> MaximumFunctionArgumentsParameter {
96      get { return (IFixedValueParameter<IntValue>)Parameters[MaximumFunctionArgumentsParameterName]; }
97    }
98    public IFixedValueParameter<PercentValue> RelativeNumberOfEvaluatedSamplesParameter {
99      get { return (IFixedValueParameter<PercentValue>)Parameters[RelativeNumberOfEvaluatedSamplesParameterName]; }
100    }
101    public IFixedValueParameter<IntRange> FitnessCalculationPartitionParameter {
102      get { return (IFixedValueParameter<IntRange>)Parameters[FitnessCalculationPartitionParameterName]; }
103    }
104    public IFixedValueParameter<IntRange> ValidationPartitionParameter {
105      get { return (IFixedValueParameter<IntRange>)Parameters[ValidationPartitionParameterName]; }
106    }
107    public IFixedValueParameter<BoolValue> ApplyLinearScalingParameter {
108      get { return (IFixedValueParameter<BoolValue>)Parameters[ApplyLinearScalingParameterName]; }
109    }
110    #endregion
111
112    #region properties
113    public string Filename { get; set; }
114    public static new Image StaticItemImage { get { return VSImageLibrary.Type; } }
115
116    IDataAnalysisProblemData IDataAnalysisProblem.ProblemData {
117      get { return ProblemData; }
118    }
119    public T ProblemData {
120      get { return ProblemDataParameter.Value; }
121      set { ProblemDataParameter.Value = value; }
122    }
123
124    public ISymbolicDataAnalysisGrammar SymbolicExpressionTreeGrammar {
125      get { return SymbolicExpressionTreeGrammarParameter.Value; }
126      set { SymbolicExpressionTreeGrammarParameter.Value = value; }
127    }
128    public ISymbolicDataAnalysisExpressionTreeInterpreter SymbolicExpressionTreeInterpreter {
129      get { return SymbolicExpressionTreeInterpreterParameter.Value; }
130      set { SymbolicExpressionTreeInterpreterParameter.Value = value; }
131    }
132
133    public IntValue MaximumSymbolicExpressionTreeDepth {
134      get { return MaximumSymbolicExpressionTreeDepthParameter.Value; }
135    }
136    public IntValue MaximumSymbolicExpressionTreeLength {
137      get { return MaximumSymbolicExpressionTreeLengthParameter.Value; }
138    }
139    public IntValue MaximumFunctionDefinitions {
140      get { return MaximumFunctionDefinitionsParameter.Value; }
141    }
142    public IntValue MaximumFunctionArguments {
143      get { return MaximumFunctionArgumentsParameter.Value; }
144    }
145    public PercentValue RelativeNumberOfEvaluatedSamples {
146      get { return RelativeNumberOfEvaluatedSamplesParameter.Value; }
147    }
148
149    public IntRange FitnessCalculationPartition {
150      get { return FitnessCalculationPartitionParameter.Value; }
151    }
152    public IntRange ValidationPartition {
153      get { return ValidationPartitionParameter.Value; }
154    }
155    public BoolValue ApplyLinearScaling {
156      get { return ApplyLinearScalingParameter.Value; }
157    }
158    #endregion
159
160    [StorableConstructor]
161    protected SymbolicDataAnalysisProblem(bool deserializing) : base(deserializing) { }
162    [StorableHook(HookType.AfterDeserialization)]
163    private void AfterDeserialization() {
164      if (!Parameters.ContainsKey(ApplyLinearScalingParameterName)) {
165        Parameters.Add(new FixedValueParameter<BoolValue>(ApplyLinearScalingParameterName, ApplyLinearScalingParameterDescription, new BoolValue(false)));
166        ApplyLinearScalingParameter.Hidden = true;
167
168        //it is assumed that for all symbolic regression algorithms linear scaling was set to true
169        //there is no possibility to determine the previous value of the parameter as it was stored in the evaluator
170        if (GetType().Name.Contains("SymbolicRegression"))
171          ApplyLinearScaling.Value = true;
172      }
173
174      RegisterEventHandlers();
175    }
176    protected SymbolicDataAnalysisProblem(SymbolicDataAnalysisProblem<T, U, V> original, Cloner cloner)
177      : base(original, cloner) {
178      RegisterEventHandlers();
179    }
180
181    protected SymbolicDataAnalysisProblem(T problemData, U evaluator, V solutionCreator)
182      : base(evaluator, solutionCreator) {
183      Parameters.Add(new ValueParameter<T>(ProblemDataParameterName, ProblemDataParameterDescription, problemData));
184      Parameters.Add(new ValueParameter<ISymbolicDataAnalysisGrammar>(SymbolicExpressionTreeGrammarParameterName, SymbolicExpressionTreeGrammarParameterDescription));
185      Parameters.Add(new ValueParameter<ISymbolicDataAnalysisExpressionTreeInterpreter>(SymbolicExpressionTreeInterpreterParameterName, SymoblicExpressionTreeInterpreterParameterDescription));
186      Parameters.Add(new FixedValueParameter<IntValue>(MaximumSymbolicExpressionTreeDepthParameterName, MaximumSymbolicExpressionTreeDepthParameterDescription));
187      Parameters.Add(new FixedValueParameter<IntValue>(MaximumSymbolicExpressionTreeLengthParameterName, MaximumSymbolicExpressionTreeLengthParameterDescription));
188      Parameters.Add(new FixedValueParameter<IntValue>(MaximumFunctionDefinitionsParameterName, MaximumFunctionDefinitionsParameterDescription));
189      Parameters.Add(new FixedValueParameter<IntValue>(MaximumFunctionArgumentsParameterName, MaximumFunctionArgumentsParameterDescription));
190      Parameters.Add(new FixedValueParameter<IntRange>(FitnessCalculationPartitionParameterName, FitnessCalculationPartitionParameterDescription));
191      Parameters.Add(new FixedValueParameter<IntRange>(ValidationPartitionParameterName, ValidationPartitionParameterDescription));
192      Parameters.Add(new FixedValueParameter<PercentValue>(RelativeNumberOfEvaluatedSamplesParameterName, RelativeNumberOfEvaluatedSamplesParameterDescription, new PercentValue(1)));
193      Parameters.Add(new FixedValueParameter<BoolValue>(ApplyLinearScalingParameterName, ApplyLinearScalingParameterDescription, new BoolValue(false)));
194
195      SymbolicExpressionTreeInterpreterParameter.Hidden = true;
196      MaximumFunctionArgumentsParameter.Hidden = true;
197      MaximumFunctionDefinitionsParameter.Hidden = true;
198      ApplyLinearScalingParameter.Hidden = true;
199
200      SymbolicExpressionTreeGrammar = new TypeCoherentExpressionGrammar();
201      SymbolicExpressionTreeInterpreter = new SymbolicDataAnalysisExpressionTreeLinearInterpreter();
202
203      FitnessCalculationPartition.Start = ProblemData.TrainingPartition.Start;
204      FitnessCalculationPartition.End = ProblemData.TrainingPartition.End;
205
206      InitializeOperators();
207
208      UpdateGrammar();
209      RegisterEventHandlers();
210    }
211
212    protected virtual void UpdateGrammar() {
213      SymbolicExpressionTreeGrammar.MaximumFunctionArguments = MaximumFunctionArguments.Value;
214      SymbolicExpressionTreeGrammar.MaximumFunctionDefinitions = MaximumFunctionDefinitions.Value;
215      foreach (var varSymbol in SymbolicExpressionTreeGrammar.Symbols.OfType<HeuristicLab.Problems.DataAnalysis.Symbolic.Variable>()) {
216        if (!varSymbol.Fixed) {
217          varSymbol.AllVariableNames = ProblemData.InputVariables.Select(x => x.Value);
218          varSymbol.VariableNames = ProblemData.AllowedInputVariables;
219        }
220      }
221      foreach (var varSymbol in SymbolicExpressionTreeGrammar.Symbols.OfType<HeuristicLab.Problems.DataAnalysis.Symbolic.VariableCondition>()) {
222        if (!varSymbol.Fixed) {
223          varSymbol.AllVariableNames = ProblemData.InputVariables.Select(x => x.Value);
224          varSymbol.VariableNames = ProblemData.AllowedInputVariables;
225        }
226      }
227    }
228
229    private void InitializeOperators() {
230      Operators.AddRange(ApplicationManager.Manager.GetInstances<ISymbolicExpressionTreeOperator>());
231      Operators.AddRange(ApplicationManager.Manager.GetInstances<ISymbolicDataAnalysisExpressionCrossover<T>>());
232      Operators.Add(new SymbolicExpressionSymbolFrequencyAnalyzer());
233      Operators.Add(new SymbolicDataAnalysisVariableFrequencyAnalyzer());
234      Operators.Add(new MinAverageMaxSymbolicExpressionTreeLengthAnalyzer());
235      Operators.Add(new SymbolicExpressionTreeLengthAnalyzer());
236      Operators.Add(new SymbolicDataAnalysisGenealogyAnalyzer());
237      ParameterizeOperators();
238    }
239
240    #region events
241    private void RegisterEventHandlers() {
242      ProblemDataParameter.ValueChanged += new EventHandler(ProblemDataParameter_ValueChanged);
243      ProblemDataParameter.Value.Changed += (object sender, EventArgs e) => OnProblemDataChanged();
244
245      SymbolicExpressionTreeGrammarParameter.ValueChanged += new EventHandler(SymbolicExpressionTreeGrammarParameter_ValueChanged);
246
247      MaximumFunctionArguments.ValueChanged += new EventHandler(ArchitectureParameterValue_ValueChanged);
248      MaximumFunctionDefinitions.ValueChanged += new EventHandler(ArchitectureParameterValue_ValueChanged);
249      MaximumSymbolicExpressionTreeDepth.ValueChanged += new EventHandler(MaximumSymbolicExpressionTreeDepth_ValueChanged);
250    }
251
252    private void ProblemDataParameter_ValueChanged(object sender, EventArgs e) {
253      ValidationPartition.Start = 0;
254      ValidationPartition.End = 0;
255      ProblemDataParameter.Value.Changed += (object s, EventArgs args) => OnProblemDataChanged();
256      OnProblemDataChanged();
257    }
258
259    private void SymbolicExpressionTreeGrammarParameter_ValueChanged(object sender, EventArgs e) {
260      UpdateGrammar();
261    }
262
263    private void ArchitectureParameterValue_ValueChanged(object sender, EventArgs e) {
264      UpdateGrammar();
265    }
266
267    private void MaximumSymbolicExpressionTreeDepth_ValueChanged(object sender, EventArgs e) {
268      if (MaximumSymbolicExpressionTreeDepth != null && MaximumSymbolicExpressionTreeDepth.Value < 3)
269        MaximumSymbolicExpressionTreeDepth.Value = 3;
270    }
271
272    protected override void OnSolutionCreatorChanged() {
273      base.OnSolutionCreatorChanged();
274      SolutionCreator.SymbolicExpressionTreeParameter.ActualNameChanged += new EventHandler(SolutionCreator_SymbolicExpressionTreeParameter_ActualNameChanged);
275      ParameterizeOperators();
276    }
277
278    private void SolutionCreator_SymbolicExpressionTreeParameter_ActualNameChanged(object sender, EventArgs e) {
279      ParameterizeOperators();
280    }
281
282    protected override void OnEvaluatorChanged() {
283      base.OnEvaluatorChanged();
284      ParameterizeOperators();
285    }
286
287    public event EventHandler ProblemDataChanged;
288    protected virtual void OnProblemDataChanged() {
289      FitnessCalculationPartition.Start = ProblemData.TrainingPartition.Start;
290      FitnessCalculationPartition.End = ProblemData.TrainingPartition.End;
291
292      UpdateGrammar();
293      ParameterizeOperators();
294
295      var handler = ProblemDataChanged;
296      if (handler != null) handler(this, EventArgs.Empty);
297
298      OnReset();
299    }
300    #endregion
301
302    protected virtual void ParameterizeOperators() {
303      var operators = Parameters.OfType<IValueParameter>().Select(p => p.Value).OfType<IOperator>().Union(Operators).ToList();
304
305      foreach (var op in operators.OfType<ISymbolicExpressionTreeGrammarBasedOperator>()) {
306        op.SymbolicExpressionTreeGrammarParameter.ActualName = SymbolicExpressionTreeGrammarParameter.Name;
307      }
308      foreach (var op in operators.OfType<ISymbolicExpressionTreeSizeConstraintOperator>()) {
309        op.MaximumSymbolicExpressionTreeDepthParameter.ActualName = MaximumSymbolicExpressionTreeDepthParameter.Name;
310        op.MaximumSymbolicExpressionTreeLengthParameter.ActualName = MaximumSymbolicExpressionTreeLengthParameter.Name;
311      }
312      foreach (var op in operators.OfType<ISymbolicExpressionTreeArchitectureAlteringOperator>()) {
313        op.MaximumFunctionArgumentsParameter.ActualName = MaximumFunctionArgumentsParameter.Name;
314        op.MaximumFunctionDefinitionsParameter.ActualName = MaximumFunctionDefinitionsParameter.Name;
315      }
316      foreach (var op in operators.OfType<ISymbolicDataAnalysisEvaluator<T>>()) {
317        op.ProblemDataParameter.ActualName = ProblemDataParameterName;
318        op.SymbolicExpressionTreeParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
319        op.EvaluationPartitionParameter.ActualName = FitnessCalculationPartitionParameter.Name;
320        op.RelativeNumberOfEvaluatedSamplesParameter.ActualName = RelativeNumberOfEvaluatedSamplesParameter.Name;
321        op.ApplyLinearScalingParameter.ActualName = ApplyLinearScalingParameter.Name;
322      }
323      foreach (var op in operators.OfType<ISymbolicExpressionTreeCrossover>()) {
324        op.ParentsParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
325        op.ChildParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
326      }
327      foreach (var op in operators.OfType<ISymbolicExpressionTreeManipulator>()) {
328        op.SymbolicExpressionTreeParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
329      }
330      foreach (var op in operators.OfType<ISymbolicExpressionTreeAnalyzer>()) {
331        op.SymbolicExpressionTreeParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
332      }
333      foreach (var op in operators.OfType<ISymbolicDataAnalysisSingleObjectiveAnalyzer>()) {
334        op.ApplyLinearScalingParameter.ActualName = ApplyLinearScalingParameter.Name;
335      }
336      foreach (var op in operators.OfType<ISymbolicDataAnalysisMultiObjectiveAnalyzer>()) {
337        op.ApplyLinearScalingParameter.ActualName = ApplyLinearScalingParameter.Name;
338      }
339      foreach (var op in operators.OfType<ISymbolicDataAnalysisAnalyzer>()) {
340        op.SymbolicExpressionTreeParameter.ActualName = SolutionCreator.SymbolicExpressionTreeParameter.ActualName;
341      }
342      foreach (var op in operators.OfType<ISymbolicDataAnalysisValidationAnalyzer<U, T>>()) {
343        op.RelativeNumberOfEvaluatedSamplesParameter.ActualName = RelativeNumberOfEvaluatedSamplesParameter.Name;
344        op.ValidationPartitionParameter.ActualName = ValidationPartitionParameter.Name;
345      }
346      foreach (var op in operators.OfType<ISymbolicDataAnalysisInterpreterOperator>()) {
347        op.SymbolicDataAnalysisTreeInterpreterParameter.ActualName = SymbolicExpressionTreeInterpreterParameter.Name;
348      }
349      foreach (var op in operators.OfType<ISymbolicDataAnalysisExpressionCrossover<T>>()) {
350        op.EvaluationPartitionParameter.ActualName = FitnessCalculationPartitionParameter.Name;
351        op.ProblemDataParameter.ActualName = ProblemDataParameter.Name;
352        op.EvaluationPartitionParameter.ActualName = FitnessCalculationPartitionParameter.Name;
353        op.RelativeNumberOfEvaluatedSamplesParameter.ActualName = RelativeNumberOfEvaluatedSamplesParameter.Name;
354        op.EvaluatorParameter.ActualName = EvaluatorParameter.Name;
355      }
356      // add tracking analyzer
357      foreach (var op in operators.OfType<SymbolicDataAnalysisGenealogyAnalyzer>()) {
358        op.BeforeCrossoverOperator = new SymbolicDataAnalysisExpressionBeforeCrossoverOperator();
359        op.AfterCrossoverOperator = new SymbolicDataAnalysisExpressionAfterCrossoverOperator();
360        op.BeforeManipulatorOperator = new BeforeManipulatorOperator<ISymbolicExpressionTree>();
361        op.AfterManipulatorOperator = new AfterManipulatorOperator<ISymbolicExpressionTree>();
362        // get crossover parameter names
363        var crossover = operators.OfType<ISymbolicExpressionTreeCrossover>().FirstOrDefault();
364        if (crossover != null) {
365          op.CrossoverParentsParameterName = crossover.ParentsParameter.Name;
366          op.CrossoverChildParameterName = crossover.ChildParameter.Name;
367        }
368        // get munipulator parameter names
369        var manipulator = operators.OfType<ISymbolicExpressionTreeManipulator>().FirstOrDefault();
370        if (manipulator != null) {
371          op.ManipulatorChildParameterName = manipulator.SymbolicExpressionTreeParameter.Name;
372        }
373        var creator = operators.OfType<ISymbolicExpressionTreeCreator>().FirstOrDefault();
374        if (creator != null) {
375          op.PopulationParameter.ActualName = creator.SymbolicExpressionTreeParameter.ActualName;
376        }
377      }
378    }
379
380    #region Import & Export
381    public virtual void Load(T data) {
382      Name = data.Name;
383      Description = data.Description;
384      ProblemData = data;
385    }
386
387    public virtual T Export() {
388      return ProblemData;
389    }
390    #endregion
391  }
392}
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