code: def test_violin_multi(self):
      violin = Violin(
          (np.random.randint(0, 2, 100), np.random.rand(100)),
          kdims=["A"],
      ).sort()
      r1, r2 = violin.range(1)
      plot = mpl_renderer.get_plot(violin)
      data, style, axis_opts = plot.get_data(violin, {}, {})
      self.assertEqual(
          data[0][0], violin.select(A=0).dimension_values(1)
      )
      self.assertEqual(
          data[0][1], violin.select(A=1).dimension_values(1)
      )
      self.assertEqual(style["positions"], [0, 1])
      self.assertEqual(style["labels"], ["0", "1"])
  
file_path: holoviews/holoviews/tests/plotting/matplotlib/test_violinplot.py
imports: import numpy
  from holoviews.element import Violin
  from .test_plot import TestMPLPlot, mpl_renderer
label_desc: Use image node_id 3 for calling the TestMPLViolinPlot obj's underlying member method code with example usage: obj.test_violin_multi() without return types