def test_dihedral_angles_min_max():
    # Create 3D mesh with regular tetrahedron
    mesh = UnitCubeMesh(MPI.comm_world, 2, 2, 2)
    dang_min, dang_max = MeshQuality.dihedral_angles_min_max(mesh)
    assert round(dang_min * (180 / pi) - 45.0) == 0
    assert round(dang_max * (180 / pi) - 90.0) == 0