Question: who has the most wins in boxing without a loss
[{'answer': 'Chávez', 'provenance': [{'wikipedia_id': '82394', 'title': 'Julio César Chávez', 'start_paragraph_id': 0, 'start_character': 12, 'end_paragraph_id': 0, 'end_character': 18, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '82394', 'title': 'Julio César Chávez', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 696, 'bleu_score': 0.6677803831225051, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14185998232884869603}, 'section': 'Section::::Abstract.'}]}]