Question: who was the actor who played darth vader
[{'answer': 'David Charles Prowse'}, {'provenance': [{'wikipedia_id': '991844', 'title': 'David Prowse', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 596, 'bleu_score': 0.9463989069388911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18203714115282255542}, 'section': 'Section::::Abstract.'}]}]