code: def test_show_contour():
      """
      This test only verifies that code up to the point of plotting with
      matplotlib works correctly.  Tests do not exercise matplotlib.
      """
      with rasterio.open("tests/data/RGB.byte.tif") as src:
          try:
              show((src, 1), contour=True)
              fig = plt.gcf()
              plt.close(fig)
          except ImportError:
              pass
  
imports: import pytest
  import matplotlib
  import numpy
  import rasterio
  from rasterio.plot import show, show_hist, get_plt, plotting_extent, adjust_band
  from rasterio.enums import ColorInterp
label_desc: Use image node_id 15 for calling a global function with example usage: test_show_contour() without return types