Question: when did the san francisco 49ers win their last super bowl
[{'answer': '1994', 'provenance': [{'wikipedia_id': '27169', 'title': 'San Francisco 49ers', 'start_paragraph_id': 3, 'start_character': 61, 'end_paragraph_id': 3, 'end_character': 65, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]