Method has_hessian_matrix

interfaces/Python/cpp_classes/PythonModel.cpp:44–46

   }

   bool PythonModel::has_hessian_matrix() const {
      return this->user_model.lagrangian_hessian.has_value();
   }

   double PythonModel::evaluate_objective(const Vector<double>& x) const {
      double objective_value = 0.;