Question: who wrote the libretto for dido and aeneas
[{'answer': 'Nahum Tate', 'provenance': [{'wikipedia_id': '650560', 'title': 'Dido and Aeneas', 'start_paragraph_id': 1, 'start_character': 140, 'end_paragraph_id': 1, 'end_character': 150, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '650560', 'title': 'Dido and Aeneas', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 916, 'bleu_score': 0.93351536383774, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14733532165016713791}, 'section': 'Section::::Abstract.'}]}]