code: def test_contours_linear_color_op_update(self):
      contours = HoloMap(
          {
              0: Contours(
                  [
                      {
                          ("x", "y"): [(0, 0), (0, 1), (1, 0)],
                          "color": 7,
                      },
                      {
                          ("x", "y"): [(1, 0), (1, 1), (0, 1)],
                          "color": 3,
                      },
                  ],
                  vdims="color",
              ),
              1: Contours(
                  [
                      {
                          ("x", "y"): [(0, 0), (0, 1), (1, 0)],
                          "color": 5,
                      },
                      {
                          ("x", "y"): [(1, 0), (1, 1), (0, 1)],
                          "color": 2,
                      },
                  ],
                  vdims="color",
              ),
          }
      ).opts(color="color", framewise=True)
      plot = bokeh_renderer.get_plot(contours)
      cds = plot.handles["source"]
      glyph = plot.handles["glyph"]
      cmapper = plot.handles["color_color_mapper"]
      plot.update((0,))
      self.assertEqual(
          property_to_dict(glyph.line_color),
          {"field": "color", "transform": cmapper},
      )
      self.assertEqual(cds.data["color"], np.array([7, 3]))
      self.assertEqual(cmapper.low, 3)
      self.assertEqual(cmapper.high, 7)
      plot.update((1,))
      self.assertEqual(cds.data["color"], np.array([5, 2]))
      self.assertEqual(cmapper.low, 2)
      self.assertEqual(cmapper.high, 5)
  
imports: import datetime
  import numpy
  import pandas
  from bokeh.models import CategoricalColorMapper, LinearColorMapper
  from holoviews.core import HoloMap, NdOverlay
  from holoviews.core.options import Cycle
  from holoviews.element import Contours, Path, Polygons
  from holoviews.plotting.bokeh.util import property_to_dict
  from holoviews.streams import PolyDraw
  from holoviews.util.transform import dim
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 5 for calling the TestContoursPlot obj's underlying member method code with example usage: obj.test_contours_linear_color_op_update() without return types