Question: who plays eustace in voyage of the dawn treader
[{'answer': 'William Jack Poulter', 'provenance': [{'wikipedia_id': '18072854', 'title': 'Will Poulter', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 20, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18072854', 'title': 'Will Poulter', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 345, 'bleu_score': 0.6291129393985291, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4243723186113403622}, 'section': 'Section::::Abstract.'}]}]