Question: who was the winning coach on the voice last season
[{'answer': 'Alicia Keys', 'provenance': [{'wikipedia_id': '31015127', 'title': 'The Voice (American TV series)', 'start_paragraph_id': 3, 'start_character': 557, 'end_paragraph_id': 3, 'end_character': 568, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]