Question: who has won the chennai open atp men's singles
[{'answer': 'Jordan Thompson', 'provenance': [{'wikipedia_id': '56527547', 'title': '2018 Chennai Open Challenger', 'start_paragraph_id': 20, 'start_character': 12, 'end_paragraph_id': 20, 'end_character': 27, 'bleu_score': 1.0, 'section': 'Section::::Champions.:Singles.\n'}]}]