code: def test_unknown_image(tmp_path):
      with open(tmp_path / "foo.unknown", "w") as file:
          file.write(
              "This image, which is actually no image, has an unknown image type."
          )
  
      with pytest.raises(InitializationError):
          r = Request(tmp_path / "foo.unknown", "r")
          PillowPlugin(r)
  
imports: import io
  import os
  from pathlib import Path
  import imageio.v3
  import numpy
  import pytest
  from imageio.core.request import InitializationError, Request
  from imageio.core.v3_plugin_api import PluginV3
  from imageio.plugins.pillow import PillowPlugin
  from PIL import Image, ImageSequence, ImageOps, __version__
label_desc: Use image node_id 18 for calling a global function with example usage: test_unknown_image(tmp_path) without return types