def METHOD_NAME():
    p = thermal_block_problem((2, 2)).with_(
        dirichlet_data=ExpressionFunction('x[0]', 2),
        outputs=[('l2', ConstantFunction(1., 2))]
    )
    m, _ = discretize_stationary_cg(p, diameter=1/10)
    U_aff = m.solve([1, 1, 1, 1])
    m_deaff = m.deaffinize(U_aff)
    mu = m.parameters.parse([0.1, 10, 7, 1])
    U = m.solve(mu)
    U_deaff = m_deaff.solve(mu)
    assert np.all(almost_equal(U, U_deaff + U_aff))
    assert np.allclose(m.output(mu), m_deaff.output(mu))