Question: when did roger federer win the french open
[{'answer': '2009', 'provenance': [{'wikipedia_id': '262376', 'title': 'Roger Federer', 'start_paragraph_id': 9, 'start_character': 337, 'end_paragraph_id': 9, 'end_character': 341, 'bleu_score': 1.0, 'section': 'Section::::Personal life.:Family.\n'}]}]