class_docstr: Tests for gov_report dataset.
code: def test_flatten_structures_html(self):
      self.assertEqual(
          gov_report._flatten_structure(
              json.loads(_REPORT), "\n", 1, True
          ),
          "<h1></h1>\n<h2>Introduction</h2>\np1\np2\n<h3>Background</h3>\np3\n<h2>Conclusion</h2>\np6",
      )
  
imports: import json
  import tensorflow_datasets.public_api
  from tensorflow_datasets.summarization.gov_report import gov_report
label_desc: Use image node_id 2 for calling the GovReportTest obj's underlying member method code with example usage: obj.test_flatten_structures_html() without return types