code: def test_curve_color_mapping_error(self):
      curve = Curve([1, 2, 3]).opts(color="x")
      with self.assertRaises(ValueError):
          self._get_plot_state(curve)
  
imports: import numpy
  from holoviews.element import Curve, Tiles
  from .test_plot import TestPlotlyPlot
label_desc: Use image node_id 5 for calling the TestCurvePlot obj's underlying member method code with example usage: obj.test_curve_color_mapping_error() without return types