code: def plot_normals(self, show_mesh=True, mag=1.0, flip=False,
                       use_every=1, **kwargs):
          
          plotter = vtki.Plotter(off_screen=kwargs.pop('off_screen', False),
                                 notebook=kwargs.pop('notebook', None))
          if show_mesh:
              plotter.add_mesh(self, **kwargs)
  
          normals = self.point_normals
          if flip:
              normals *= -1
          plotter.add_arrows(self.points[::use_every],
                             normals[::use_every], mag=mag)
          return plotter.show()
docs: Plot the point normals of a mesh.