code: def test_signature(tmpdir):
      """
      Test the SHA 256 signature of a temporary file
      """
  
      fpath = tmpdir.join("test.json")
      json.dump(FIXTURE, fpath, indent=2)
      assert (
          sha256sum(str(fpath))
          == "d10b36aa74a59bcf4a88185837f658afaf3646eff2bb16c3928d0e9335e945d2"
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_signature(tmpdir) without return types