Question: who is the lead singer for the mavericks
[{'answer': 'Raul Malo', 'provenance': [{'wikipedia_id': '1852433', 'title': 'The Mavericks', 'start_paragraph_id': 2, 'start_character': 118, 'end_paragraph_id': 2, 'end_character': 127, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]