Question: who is the main character in sonny's blues
[{'answer': "Sonny 's brother", 'provenance': [{'wikipedia_id': '6164012', 'title': "Sonny's Blues", 'start_paragraph_id': 1, 'start_character': 241, 'end_paragraph_id': 1, 'end_character': 260, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]