code: def test_labelbase():
      # Remove this line when this test image is regenerated.
      plt.rcParams["text.kerning_factor"] = 6
  
      fig, ax = plt.subplots()
  
      ax.plot([0.5], [0.5], "o")
  
      label = LabelBase(0.5, 0.5, "Test")
      label._ref_angle = -90
      label._offset_radius = 50
      label.set_rotation(-90)
      label.set(ha="center", va="top")
      ax.add_artist(label)
  
file_path: matplotlib/lib/mpl_toolkits/axisartist/tests/test_axis_artist.py
imports: import matplotlib.pyplot
  from matplotlib.testing.decorators import image_comparison
  from mpl_toolkits.axisartist import AxisArtistHelperRectlinear
  from mpl_toolkits.axisartist.axis_artist import AxisArtist, AxisLabel, LabelBase, Ticks, TickLabels
label_desc: Use image node_id 2 for calling a global function with example usage: test_labelbase() without return types