Question: when was the last time mt etna erupted
[{'answer': '16 March 2017', 'provenance': [{'wikipedia_id': '169351', 'title': 'Mount Etna', 'start_paragraph_id': 38, 'start_character': 15, 'end_paragraph_id': 38, 'end_character': 28, 'bleu_score': 1.0, 'section': 'Section::::History of volcanic eruptions.:Eruptions.:Recent eruptions.\n'}]}]