code: def test_quadmesh_update_cbar(self):
      xs = ys = np.linspace(0, 6, 10)
      zs = np.linspace(1, 2, 5)
      XS, _YS, ZS = np.meshgrid(xs, ys, zs)
      values = np.sin(XS) * ZS
      ds = Dataset((xs, ys, zs, values.T), ["x", "y", "z"], "values")
      hmap = ds.to(QuadMesh).opts(colorbar=True, framewise=True)
      plot = mpl_renderer.get_plot(hmap)
      cbar = plot.handles["cbar"]
      np.testing.assert_allclose(
          [cbar.vmin, cbar.vmax],
          [-0.9989549170979283, 0.9719379013633128],
      )
      plot.update(3)
      np.testing.assert_allclose(
          [cbar.vmin, cbar.vmax],
          [-1.7481711049213744, 1.7008913273857975],
      )
  
file_path: holoviews/holoviews/tests/plotting/matplotlib/test_quadmeshplot.py
imports: import numpy
  from holoviews.element import Dataset, Image, QuadMesh
  from .test_plot import TestMPLPlot, mpl38, mpl_renderer
label_desc: Use image node_id 4 for calling the TestQuadMeshPlot obj's underlying member method code with example usage: obj.test_quadmesh_update_cbar() without return types