Question: when did burning man move to black rock
[{'answer': '1997', 'provenance': [{'wikipedia_id': '203785', 'title': 'Burning Man', 'start_paragraph_id': 2, 'start_character': 185, 'end_paragraph_id': 2, 'end_character': 189, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '203785', 'title': 'Burning Man', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 615, 'bleu_score': 0.716736994434081, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9015622780040694686}, 'section': 'Section::::Abstract.'}]}]