Question: who came out first iron man or batman
[{'answer': 'Batman', 'provenance': [{'wikipedia_id': '1217448', 'title': 'First appearance', 'start_paragraph_id': 4, 'start_character': 96, 'end_paragraph_id': 4, 'end_character': 102, 'bleu_score': 1.0, 'section': 'Section::::Reader interest in first appearances.\n'}]}]