code: def test_identity():
      arr = np.array([[1.0, 2.0, 3.0]])
      actual = arr
      expected = util.identity(arr)
      assert matrix.every_nd(bool, expected == actual)
  
imports: import numpy
  from impyute.ops import matrix
  from impyute.ops import util
label_desc: Use image node_id 4 for calling a global function with example usage: test_identity() without return types