Question: what does a camshaft do for your car
[{'answer': 'used to operate poppet valves', 'provenance': [{'wikipedia_id': '147572', 'title': 'Camshaft', 'start_paragraph_id': 6, 'start_character': 61, 'end_paragraph_id': 6, 'end_character': 90, 'bleu_score': 1.0, 'section': 'Section::::Uses.\n'}]}, {'provenance': [{'wikipedia_id': '147572', 'title': 'Camshaft', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 348, 'bleu_score': 0.9669306597086381, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17481516172710745225}, 'section': 'Section::::Uses.\n'}]}]