Question: who was the longest reigning pope in church history
[{'answer': 'Pope Pius IX', 'provenance': [{'wikipedia_id': '54161', 'title': 'Pope Pius IX', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '54161', 'title': 'Pope Pius IX', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 458, 'bleu_score': 0.8900620841790461, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2144831419272339859}, 'section': 'Section::::Abstract.'}]}]