code: def test_should_save_output_grid(output_dir):
      grid = np.random.random((208, 208))
  
      explainer = ExtractActivations()
      explainer.save(grid, output_dir, "output.png")
  
      assert len(list(output_dir.glob("output.png"))) == 1
  
imports: import numpy
  from tf_explain.core.activations import ExtractActivations
label_desc: Use image node_id 3 for calling a global function with example usage: test_should_save_output_grid(output_dir) without return types