Question: when were elephants first used in the circus
[{'answer': 'early eighteenth century', 'provenance': [{'wikipedia_id': '156999', 'title': 'Circus', 'start_paragraph_id': 40, 'start_character': 128, 'end_paragraph_id': 40, 'end_character': 152, 'bleu_score': 1.0, 'section': 'Section::::Performance.:Animal acts.\n'}]}, {'provenance': [{'wikipedia_id': '156999', 'title': 'Circus', 'start_paragraph_id': 40, 'start_character': 0, 'end_paragraph_id': 40, 'end_character': 587, 'bleu_score': 0.979896933041101, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17395459688296156815}, 'section': 'Section::::Performance.:Animal acts.\n'}]}]