Question: what was the attendance at the 2017 belmont stakes
[{'answer': '57,729', 'provenance': [{'wikipedia_id': '53985623', 'title': '2017 Belmont Stakes', 'start_paragraph_id': 9, 'start_character': 75, 'end_paragraph_id': 9, 'end_character': 81, 'bleu_score': 1.0, 'section': 'Section::::Race description.\n'}]}]