code: def test_parse_xml_string(self):
      cand_pairs = parse_xml_string(_CAND_XML_STR)
      self.assertLen(cand_pairs, len(_EXPECTED_PAIRS))
      self.assertEqual(_EXPECTED_PAIRS, cand_pairs)
  
imports: from tensorflow_datasets import testing
  from tensorflow_datasets.datasets.assin2.assin2_utils import Pair
  from tensorflow_datasets.datasets.assin2.assin2_utils import parse_xml_string
label_desc: Use image node_id 1 for calling the Assin2UtilsTest obj's underlying member method code with example usage: obj.test_parse_xml_string() without return types