code: def test_contours_line_width_op_update(self):
      contours = HoloMap(
          {
              0: Contours(
                  [
                      {
                          ("x", "y"): [(0, 0), (0, 1), (1, 0)],
                          "line_width": 7,
                      },
                      {
                          ("x", "y"): [(1, 0), (1, 1), (0, 1)],
                          "line_width": 3,
                      },
                  ],
                  vdims="line_width",
              ),
              1: Contours(
                  [
                      {
                          ("x", "y"): [(0, 0), (0, 1), (1, 0)],
                          "line_width": 2,
                      },
                      {
                          ("x", "y"): [(1, 0), (1, 1), (0, 1)],
                          "line_width": 5,
                      },
                  ],
                  vdims="line_width",
              ),
          }
      ).opts(linewidth="line_width", framewise=True)
      plot = mpl_renderer.get_plot(contours)
      artist = plot.handles["artist"]
      self.assertEqual(artist.get_linewidths(), [7, 3])
      plot.update((1,))
      self.assertEqual(artist.get_linewidths(), [2, 5])
  
imports: import numpy
  import pytest
  from holoviews.core import NdOverlay
  from holoviews.core.options import AbbreviatedException
  from holoviews.core.spaces import HoloMap
  from holoviews.element import Contours, Path, Polygons
  from .test_plot import TestMPLPlot, mpl_renderer
label_desc: Use image node_id 9 for calling the TestContoursPlot obj's underlying member method code with example usage: obj.test_contours_line_width_op_update() without return types