code: def test_labels_simple(self):
      labels = Labels([(0, 1, "A"), (1, 0, "B")])
      plot = mpl_renderer.get_plot(labels)
      artist = plot.handles["artist"]
      expected = {
          "x": np.array([0, 1]),
          "y": np.array([1, 0]),
          "Label": ["A", "B"],
      }
      for i, text in enumerate(artist):
          self.assertEqual(text._x, expected["x"][i])
          self.assertEqual(text._y, expected["y"][i])
          self.assertEqual(text.get_text(), expected["Label"][i])
  
imports: import numpy
  from holoviews.core.dimension import Dimension
  from holoviews.core.options import Cycle
  from holoviews.core.spaces import HoloMap
  from holoviews.element import Labels
  from holoviews.plotting.util import rgb2hex
  from .test_plot import TestMPLPlot, mpl_renderer
label_desc: Use image node_id 1 for calling the TestLabelsPlot obj's underlying member method code with example usage: obj.test_labels_simple() without return types