code: def test_tag_register_type():
      """Test the specification of the tag register. See _tags for specs."""
      assert isinstance(ESTIMATOR_TAG_REGISTER, list)
      assert all(
          isinstance(tag, tuple) for tag in ESTIMATOR_TAG_REGISTER
      )
  
      for tag in ESTIMATOR_TAG_REGISTER:
          assert len(tag) == 4
          assert isinstance(tag[0], str)
          assert isinstance(tag[1], (str, list))
          if isinstance(tag[1], list):
              assert all(isinstance(x, str) for x in tag[1])
          assert isinstance(tag[2], (str, tuple))
          if isinstance(tag[2], tuple):
              assert len(tag[2]) == 2
              assert isinstance(tag[2][0], str)
              assert isinstance(tag[2][1], (list, str))
              if isinstance(tag[2][1], list):
                  assert all(isinstance(x, str) for x in tag[2][1])
          assert isinstance(tag[3], str)
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_tag_register_type() without return types