Question: who plays the emperor in revenge of the sith
[{'answer': 'Ian McDiarmid', 'provenance': [{'wikipedia_id': '18426653', 'title': 'Palpatine', 'start_paragraph_id': 1, 'start_character': 270, 'end_paragraph_id': 1, 'end_character': 283, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18426653', 'title': 'Palpatine', 'start_paragraph_id': 1, 'start_character': 40, 'end_paragraph_id': 1, 'end_character': 650, 'bleu_score': 0.647239003309634, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11612584586734596867}, 'section': 'Section::::Abstract.'}]}]