Question: who played blackbeard in pirates of the caribbean 4
[{'answer': 'Ian David McShane', 'provenance': [{'wikipedia_id': '638372', 'title': 'Ian McShane', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]