code: def test_attr(self):
      result = zero_out_op_3.zero_out([5, 4, 3, 2, 1], preserve_index=3)
      self.assertAllEqual(result, [0, 0, 0, 2, 0])
  
imports: import tensorflow
  from tensorflow.examples.adding_an_op import zero_out_op_3
label_desc: Use image node_id 2 for calling the ZeroOut3Test obj's underlying member method code with example usage: obj.test_attr() without return types