Question: who is the director of the film avatar
[{'answer': 'James Cameron', 'provenance': [{'wikipedia_id': '4273140', 'title': 'Avatar (2009 film)', 'start_paragraph_id': 1, 'start_character': 20, 'end_paragraph_id': 1, 'end_character': 33, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]