def METHOD_NAME(approx_order=1):
    """Define the problem to solve."""
    from sfepy import data_dir
    filename_mesh = data_dir + '/meshes/3d/block.mesh'
    options = {
        'nls' : 'newton',
        'ls' : 'ls',
        'post_process_hook' : 'verify_tractions',
    }
    functions = {
        'linear_tension' : (linear_tension,),
    }
    fields = {
        'displacement': ('real', 3, 'Omega', approx_order),
    }
    materials = {
        'solid' : ({'D': stiffness_from_lame(3, lam=5.769, mu=3.846)},),
        'load' : (None, 'linear_tension')
    }
    variables = {
        'u' : ('unknown field', 'displacement', 0),
        'v' : ('test field', 'displacement', 'u'),
    }
    regions = {
        'Omega' : 'all',
        'Left' : ('vertices in (x < -4.99)', 'facet'),
        # Use a parent region to select only facets belonging to cells in the
        # parent region. Otherwise, each facet is in the region two times, with
        # opposite normals.
        'Middle' : ('vertices in (x > -1e-10) & (x < 1e-10)', 'facet', 'Rhalf'),
        'Rhalf' : 'vertices in x > -1e-10',
        'Right' : ('vertices in (x > 4.99)', 'facet'),
    }
    ebcs = {
        'fixb' : ('Left', {'u.all' : 0.0}),
        'fixt' : ('Right', {'u.[1,2]' : 0.0}),
    }
    integrals = {
        'i' : 2 * approx_order,
    }
    ##
    # Balance of forces.
    equations = {
        'elasticity' :
        """dw_lin_elastic.i.Omega( solid.D, v, u )
         = - dw_surface_ltr.i.Right( load.val, v )""",
    }
    ##
    # Solvers etc.
    solvers = {
        'ls' : ('ls.auto_direct', {}),
        'newton' : ('nls.newton',
                    { 'i_max'      : 1,
                      'eps_a'      : 1e-10,
                      'eps_r'      : 1.0,
                      'macheps'   : 1e-16,
                      # Linear system error < (eps_a * lin_red).
                      'lin_red'    : 1e-2,
                      'ls_red'     : 0.1,
                      'ls_red_warp' : 0.001,
                      'ls_on'      : 1.1,
                      'ls_min'     : 1e-5,
                      'check'     : 0,
                      'delta'     : 1e-6,
                      })
    }
    return locals()