How to use the pygmsh.opencascade.Geometry function in pygmsh

def test():
    geom = pygmsh.opencascade.Geometry()

    rectangle = geom.add_rectangle(
        [-1.0, -1.0, 0.0], 2.0, 2.0, corner_radius=0.2, char_length=0.05
    )
    disk1 = geom.add_disk([-1.2, 0.0, 0.0], 0.5)
    disk2 = geom.add_disk([+1.2, 0.0, 0.0], 0.5, 0.3)
    union = geom.boolean_union([rectangle, disk1, disk2])

    disk3 = geom.add_disk([0.0, -0.9, 0.0], 0.5)
    disk4 = geom.add_disk([0.0, +0.9, 0.0], 0.5)
    flat = geom.boolean_difference([union], [disk3, disk4])

    geom.extrude(flat, [0, 0, 0.3])

    ref = 1.1742114942
    mesh = pygmsh.generate_mesh(geom)

def test():
    geom = pygmsh.opencascade.Geometry(
        characteristic_length_min=0.1, characteristic_length_max=0.1
    )

    p0 = geom.add_point([-0.5, -0.5, 0], 0.01)
    p1 = geom.add_point([+0.5, -0.5, 0], 0.01)
    p2 = geom.add_point([+0.5, +0.5, 0], 0.01)
    p3 = geom.add_point([-0.5, +0.5, 0], 0.01)
    l0 = geom.add_line(p0, p1)
    l1 = geom.add_line(p1, p2)
    l2 = geom.add_line(p2, p3)
    l3 = geom.add_line(p3, p0)
    ll0 = geom.add_line_loop([l0, l1, l2, l3])
    square_builtin = geom.add_plane_surface(ll0)
    square_opencascade = geom.add_rectangle([0, 0, 0], 1.0, 1.0)
    geom.boolean_difference([square_opencascade], [square_builtin])

def test():
    geom = pygmsh.opencascade.Geometry(
        characteristic_length_min=2.0, characteristic_length_max=2.0
    )

    rect1 = geom.add_rectangle([10.0, 0.0, 0.0], 20.0, 40.0, corner_radius=5.0)
    rect2 = geom.add_rectangle([0.0, 10.0, 0.0], 40.0, 20.0, corner_radius=5.0)
    disk1 = geom.add_disk([14.5, 35.0, 0.0], 1.85)
    disk2 = geom.add_disk([25.5, 5.0, 0.0], 1.85)

    rect3 = geom.add_rectangle([10.0, 30.0, 0.0], 10.0, 1.0)
    rect4 = geom.add_rectangle([20.0, 9.0, 0.0], 10.0, 1.0)

    r1 = geom.add_rectangle([9.0, 0.0, 0.0], 21.0, 20.5, corner_radius=8.0)
    r2 = geom.add_rectangle([10.0, 00.0, 0.0], 20.0, 19.5, corner_radius=7.0)
    diff1 = geom.boolean_difference([r1], [r2])
    r22 = geom.add_rectangle([9.0, 10.0, 0.0], 11.0, 11.0)
    inter1 = geom.boolean_intersection([diff1, r22])

def test():
    geom = pygmsh.opencascade.Geometry()

    geom.add_wedge([0.0, 0.0, 0.0], [1.0, 1.0, 1.0], top_extent=0.4, char_length=0.1)

    ref = 0.7
    mesh = pygmsh.generate_mesh(geom)
    assert abs(compute_volume(mesh) - ref) < 1.0e-2 * ref
    return mesh

def test_intersection():
    geom = pygmsh.opencascade.Geometry(
        characteristic_length_min=0.1, characteristic_length_max=0.1
    )

    rectangle = geom.add_rectangle([-1.0, -1.0, 0.0], 2.0, 2.0)
    disk_w = geom.add_disk([-1.0, 0.0, 0.0], 0.5)
    disk_e = geom.add_disk([+1.0, 0.0, 0.0], 0.5)
    geom.boolean_intersection([rectangle, disk_w, disk_e])

    ref = 0.7803612
    mesh = pygmsh.generate_mesh(geom)
    assert abs(compute_volume(mesh) - ref) < 1.0e-2 * ref
    return mesh

def geom(self, lcar: float) -> Geometry:
        geom = Geometry()
        geom.add_ellipsoid([0.]*3, self.semiaxes, lcar)
        return geom

def _old_logo():
    geom = pygmsh.opencascade.Geometry(
        characteristic_length_min=0.5, characteristic_length_max=0.5
    )

    container = geom.add_rectangle([0.0, 0.0, 0.0], 10.0, 10.0)

    letter_i = geom.add_rectangle([2.0, 2.0, 0.0], 1.0, 4.5)
    i_dot = geom.add_disk([2.5, 7.5, 0.0], 0.6)

    disk1 = geom.add_disk([6.25, 4.5, 0.0], 2.5)
    disk2 = geom.add_disk([6.25, 4.5, 0.0], 1.5)
    letter_o = geom.boolean_difference([disk1], [disk2])

    geom.boolean_difference([container], [letter_i, i_dot, letter_o])

    mesh = pygmsh.generate_mesh(geom)
    X, cells = mesh.points, mesh.cells