code: def test_quadcontourset_reuse():
      # If QuadContourSet returned from one contour(f) call is passed as first
      # argument to another the underlying C++ contour generator will be reused.
      x, y = np.meshgrid([0.0, 1.0], [0.0, 1.0])
      z = x + y
      fig, ax = plt.subplots()
      qcs1 = ax.contourf(x, y, z)
      qcs2 = ax.contour(x, y, z)
      assert qcs2._contour_generator != qcs1._contour_generator
      qcs3 = ax.contour(qcs1, z)
      assert qcs3._contour_generator == qcs1._contour_generator
  
imports: import datetime
  import platform
  import re
  from unittest import mock
  import contourpy
  import numpy
  from numpy.testing import assert_array_almost_equal, assert_array_almost_equal_nulp, assert_array_equal
  import matplotlib
  from matplotlib import pyplot, rc_context, ticker
  from matplotlib.colors import LogNorm, same_color
  import matplotlib.patches
  from matplotlib.testing.decorators import check_figures_equal, image_comparison
  import pytest
label_desc: Use image node_id 28 for calling a global function with example usage: test_quadcontourset_reuse() without return types