def METHOD_NAME(self, p=2, fname='surface.vtu'):
    from fealpy.geometry import SphereSurface, EllipsoidSurface, SphereSurfaceTest
    surface = SphereSurface()
    #surface = SphereSurfaceTest()
    #surface = EllipsoidSurface()
    #surface = ScaledSurface(surface,scale=[9,3,1])
    mesh = surface.init_mesh()
    node = mesh.entity('node')
    cell = mesh.entity('cell')
    lmesh = LagrangeTriangleMesh(node, cell, p=p, surface=surface)
    NC = lmesh.number_of_cells()
    a = lmesh.cell_area()
    lmesh.to_vtk(fname=fname)