code: def test_quadmesh_colorbar(self):
      n = 21
      xs = np.logspace(1, 3, n)
      ys = np.linspace(1, 10, n)
      qmesh = QuadMesh((xs, ys, np.random.rand(n - 1, n - 1))).opts(
          colorbar=True
      )
      plot = bokeh_renderer.get_plot(qmesh)
      self.assertIsInstance(plot.handles["colorbar"], ColorBar)
      self.assertIs(
          plot.handles["colorbar"].color_mapper,
          plot.handles["color_mapper"],
      )
  
file_path: holoviews/holoviews/tests/plotting/bokeh/test_quadmeshplot.py
imports: import numpy
  from bokeh.models import ColorBar
  from holoviews.element import Image, QuadMesh
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 3 for calling the TestQuadMeshPlot obj's underlying member method code with example usage: obj.test_quadmesh_colorbar() without return types