code: def test_surface_colorbar(self):
      img = Surface(
          ([1, 2, 3], [0, 1], np.array([[0, 1, 2], [2, 3, 4]]))
      )
      img.opts(colorbar=True)
      state = self._get_plot_state(img)
      trace = state["data"][0]
      self.assertTrue(trace["showscale"])
  
      img.opts(colorbar=False)
      state = self._get_plot_state(img)
      trace = state["data"][0]
      self.assertFalse(trace["showscale"])
  
file_path: holoviews/holoviews/tests/plotting/plotly/test_surfaceplot.py
imports: import numpy
  from holoviews.element import Surface
  from .test_plot import TestPlotlyPlot
label_desc: Use image node_id 2 for calling the TestSurfacePlot obj's underlying member method code with example usage: obj.test_surface_colorbar() without return types