Question: when was the first roller coaster built in the world
[{'answer': 'July 8 , 1817', 'provenance': [{'wikipedia_id': '137471', 'title': 'Roller coaster', 'start_paragraph_id': 5, 'start_character': 96, 'end_paragraph_id': 5, 'end_character': 109, 'bleu_score': 1.0, 'section': 'Section::::History.:The Russian mountain and the Aerial Promenades.\n'}]}, {'provenance': [{'wikipedia_id': '137471', 'title': 'Roller coaster', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 289, 'bleu_score': 0.958740481558872, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7022572259401157567}, 'section': 'Section::::History.:The Russian mountain and the Aerial Promenades.\n'}]}]