can't generate JSON to Python class

[wongsatornm]

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Exception:
System.NotSupportedException: Unsupported json type: NullableDate at Xamasoft.JsonClassGenerator.CodeWriters.PythonCodeWriter.GetTypeName(JsonType type) in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\CodeWriters\PythonCodeWriter.cs:line 54 at Xamasoft.JsonClassGenerator.JsonType.GetTypeName() in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\JsonType.cs:line 157 at Xamasoft.JsonClassGenerator.CodeWriters.PythonCodeWriter.WriteClassMembers(StringBuilder sw, JsonType type, String prefix) in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\CodeWriters\PythonCodeWriter.cs:line 142 at Xamasoft.JsonClassGenerator.CodeWriters.PythonCodeWriter.WriteClass(StringBuilder sw, JsonType type) in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\CodeWriters\PythonCodeWriter.cs:line 95 at Xamasoft.JsonClassGenerator.CodeWriters.PythonCodeWriter.WriteClassesToFile(StringBuilder sw, IEnumerable`1 types, Boolean rootIsArray) in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\CodeWriters\PythonCodeWriter.cs:line 122 at Xamasoft.JsonClassGenerator.JsonClassGenerator.GenerateClasses(String jsonInput, String& errorMessage) in C:\Users\Hilal\OneDrive\Desktop\Json2CSharpCodeGenerator\JsonClassGeneratorLib\JsonClassGenerator.cs:line 78

[wongsatornm]