Question: who has won the mens doubles title at 2017 us open
[{'answer': 'Jean - Julien Rojer', 'provenance': [{'wikipedia_id': '54683070', 'title': "2017 US Open – Men's Doubles", 'start_paragraph_id': 1, 'start_character': 93, 'end_paragraph_id': 1, 'end_character': 114, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Horia Tecău', 'provenance': [{'wikipedia_id': '54683070', 'title': "2017 US Open – Men's Doubles", 'start_paragraph_id': 1, 'start_character': 115, 'end_paragraph_id': 1, 'end_character': 126, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]