code: def test_metric_hashing(metric_cls):
      """Tests that hashes are different.
  
      See the Metric's hash function for details on why this is required.
  
      """
      instance_1 = metric_cls()
      instance_2 = metric_cls()
  
      assert hash(instance_1) != hash(instance_2)
      assert id(instance_1) != id(instance_2)
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_metric_hashing(metric_cls) without return types