code: def test_triplot_return():
      # Check that triplot returns the artists it adds
      ax = plt.figure().add_subplot()
      triang = mtri.Triangulation(
          [0.0, 1.0, 0.0, 1.0],
          [0.0, 0.0, 1.0, 1.0],
          triangles=[[0, 1, 3], [3, 2, 0]],
      )
      assert (
          ax.triplot(triang, "b-") is not None
      ), "triplot should return the artist it adds"
  
imports: import numpy
  from numpy.testing import assert_array_equal, assert_array_almost_equal, assert_array_less
  import numpy.ma.testutils
  import pytest
  import matplotlib
  import matplotlib.pyplot
  import matplotlib.tri
  from matplotlib.path import Path
  from matplotlib.testing.decorators import image_comparison, check_figures_equal
label_desc: Use image node_id 27 for calling a global function with example usage: test_triplot_return() without return types