Question: who is the actor that plays professor snape
[{'answer': 'Alan Sidney Patrick Rickman', 'provenance': [{'wikipedia_id': '39879', 'title': 'Alan Rickman', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 27, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]