code: def download_sparse_points():
      
      saved_file, _ = _download_file('sparsePoints.txt')
      points_reader = vtk.vtkDelimitedTextReader()
      points_reader.SetFileName(saved_file)
      points_reader.DetectNumericColumnsOn()
      points_reader.SetFieldDelimiterCharacters('\t')
      points_reader.SetHaveHeaders(True)
      table_points = vtk.vtkTableToPolyData()
      table_points.SetInputConnection(points_reader.GetOutputPort())
      table_points.SetXColumn('x')
      table_points.SetYColumn('y')
      table_points.SetZColumn('z')
      table_points.Update()
      return vtki.wrap(table_points.GetOutput())
docs: Used with ``download_saddle_surface``