Question: who sings lonesome valley in o brother where art thou
[{'answer': 'The Fairfield Four', 'provenance': [{'wikipedia_id': '194349', 'title': 'O Brother, Where Art Thou? (soundtrack)', 'start_paragraph_id': 24, 'start_character': 12, 'end_paragraph_id': 24, 'end_character': 30, 'bleu_score': 1.0, 'section': 'Section::::Personnel.\n'}]}]