Question: who did the first open heart surgery in the world
[{'answer': 'Axel Cappelen', 'provenance': [{'wikipedia_id': '804779', 'title': 'Cardiac surgery', 'start_paragraph_id': 4, 'start_character': 295, 'end_paragraph_id': 4, 'end_character': 308, 'bleu_score': 1.0, 'section': 'Section::::History.:19th century.\n'}]}, {'provenance': [{'wikipedia_id': '804779', 'title': 'Cardiac surgery', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 684, 'bleu_score': 0.9526401996952971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3266408320505548359}, 'section': 'Section::::History.:19th century.\n'}]}]