code: def test_link_func_identity():
      predictions = np.array([[1.0, 2.25], [4.0, -6.0]])
      expected = predictions.copy()
      result = link_func(predictions, "identity")
      assert np.all(result == expected)
  
imports: import numpy
  import pytest
  from interpret.utils import link_func, inv_link
label_desc: Use image node_id 24 for calling a global function with example usage: test_link_func_identity() without return types