Question: who directed batman vs superman dawn of justice
[{'answer': 'Zack Snyder', 'provenance': [{'wikipedia_id': '2619910', 'title': 'Batman v Superman: Dawn of Justice', 'start_paragraph_id': 1, 'start_character': 255, 'end_paragraph_id': 1, 'end_character': 266, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2619910', 'title': 'Batman v Superman: Dawn of Justice', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 795, 'bleu_score': 0.8221484698549371, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4850786390278012959}, 'section': 'Section::::Abstract.'}]}]