Question: who plays bad guy in iron man 2
[{'answer': 'Justin Hammer', 'provenance': [{'wikipedia_id': '22144721', 'title': 'Iron Man 2', 'start_paragraph_id': 1, 'start_character': 925, 'end_paragraph_id': 1, 'end_character': 938, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Ivan Vanko', 'provenance': [{'wikipedia_id': '22144721', 'title': 'Iron Man 2', 'start_paragraph_id': 1, 'start_character': 736, 'end_paragraph_id': 1, 'end_character': 746, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '22144721', 'title': 'Iron Man 2', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 938, 'bleu_score': 0.9715305700167061, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16136502475439513114}, 'section': 'Section::::Abstract.'}]}]