Question: longest stage in the tour de france 2017
[{'answer': '19', 'provenance': [{'wikipedia_id': '49098974', 'title': '2017 Tour de France', 'start_paragraph_id': 1, 'start_character': 289, 'end_paragraph_id': 1, 'end_character': 291, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]