Question: who played chewbacca in star wars episode 4
[{'answer': 'Peter Mayhew', 'provenance': [{'wikipedia_id': '999975', 'title': 'Peter Mayhew', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]