Question: pope who was first sovereign of vatican city
[{'answer': 'Pius XI', 'provenance': [{'wikipedia_id': '61502', 'title': 'List of popes', 'start_paragraph_id': 22, 'start_character': 97, 'end_paragraph_id': 22, 'end_character': 104, 'bleu_score': 1.0, 'section': 'Section::::Notes on numbering of popes.\n'}]}]