code: def test_imshow():
      source_proj = ccrs.PlateCarree()
      img = plt.imread(NATURAL_EARTH_IMG)
      # Convert the image to a byte array, rather than float, which is the
      # form that JPG images would be loaded with imread.
      img = (img * 255).astype("uint8")
      ax = plt.axes(projection=ccrs.Orthographic())
      ax.imshow(img, transform=source_proj, extent=[-180, 180, -90, 90])
      return ax.figure
  
imports: import types
  import matplotlib.colors
  import matplotlib.pyplot
  import numpy
  from PIL import Image
  import pytest
  import shapely.geometry
  from cartopy import config
  import cartopy.crs
  import cartopy.io.img_tiles
  from cartopy.tests.conftest import _HAS_PYKDTREE_OR_SCIPY
  import cartopy.tests.test_img_tiles
label_desc: Use image node_id 3 for calling a global function with example usage: test_imshow() and returns: ax