def __init__(self, coordinate_system = None):
        """Create the static hyperelasticity problem"""

        # Set up parameters
        self.parameters = Parameters("problem_parameters")
        self.parameters.add(solver_parameters())
        self.coordinate_system = coordinate_system
    def __init__(self):
        """Create the hyperelasticity problem"""

        # Set up parameters
        self.parameters = Parameters("problem_parameters")
        self.parameters.add(solver_parameters())

        # Create solver later
        self.solver = None