code: def test_circular_contour_warning():
      # Check that almost circular contours don't throw a warning
      x, y = np.meshgrid(np.linspace(-2, 2, 4), np.linspace(-2, 2, 4))
      r = np.hypot(x, y)
      plt.figure()
      cs = plt.contour(x, y, r)
      plt.clabel(cs)
  
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 19 for calling a global function with example usage: test_circular_contour_warning() without return types