Question: who wrote johnny cash's song a boy named sue
[{'answer': 'Shel Silverstein', 'provenance': [{'wikipedia_id': '316851', 'title': 'A Boy Named Sue', 'start_paragraph_id': 1, 'start_character': 57, 'end_paragraph_id': 1, 'end_character': 73, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '316851', 'title': 'A Boy Named Sue', 'start_paragraph_id': 1, 'start_character': 62, 'end_paragraph_id': 1, 'end_character': 774, 'bleu_score': 0.8208268412201299, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10224109832365954820}, 'section': 'Section::::Abstract.'}]}]