Question: when did leonardo da vinci finish painting the mona lisa
[{'answer': '1517', 'provenance': [{'wikipedia_id': '70889', 'title': 'Mona Lisa', 'start_paragraph_id': 2, 'start_character': 280, 'end_paragraph_id': 2, 'end_character': 284, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '70889', 'title': 'Mona Lisa', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 518, 'bleu_score': 0.9623384567935761, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14961282333499646697}, 'section': 'Section::::Abstract.'}]}]