Question: how many times does dorothy have to clink her ruby slippers together to get home
[{'answer': 'three', 'provenance': [{'wikipedia_id': '199256', 'title': 'Ruby slippers', 'start_paragraph_id': 5, 'start_character': 1281, 'end_paragraph_id': 5, 'end_character': 1286, 'bleu_score': 1.0, 'section': 'Section::::The slippers.:"The Wizard of Oz" (1939).\n'}]}]