code: def test_area_fill_between_ys(self):
      area = Area(
          [(0, 1, 0.5), (1, 2, 1), (2, 3, 2.25)], vdims=["y", "y2"]
      )
      state = self._get_plot_state(area)
      self.assertEqual(state["data"][0]["y"], np.array([0.5, 1, 2.25]))
      self.assertEqual(state["data"][0]["mode"], "lines")
      self.assertEqual(state["data"][0].get("fill", None), None)
      self.assertEqual(state["data"][1]["y"], np.array([1, 2, 3]))
      self.assertEqual(state["data"][1]["mode"], "lines")
      self.assertEqual(state["data"][1]["fill"], "tonexty")
      self.assertEqual(state["layout"]["yaxis"]["range"], [0.5, 3])
  
file_path: holoviews/holoviews/tests/plotting/plotly/test_areaplot.py
imports: import numpy
  import pandas
  from holoviews.element import Area, Overlay
  from .test_plot import TestPlotlyPlot
label_desc: Use image node_id 3 for calling the TestAreaPlot obj's underlying member method code with example usage: obj.test_area_fill_between_ys() without return types