Question: what does unesco do for world heritage sites
[{'answer': 'practical conservation for posterity', 'provenance': [{'wikipedia_id': '44940', 'title': 'World Heritage Site', 'start_paragraph_id': 3, 'start_character': 27, 'end_paragraph_id': 3, 'end_character': 63, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '44940', 'title': 'World Heritage Site', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 479, 'bleu_score': 0.849826577454302, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10146575495115629618}, 'section': 'Section::::Abstract.'}]}]