Question: what is the latest version of iphone ios
[{'answer': 'iOS 11.2. 1'}, {'provenance': [{'wikipedia_id': '18195583', 'title': 'IOS version history', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 751, 'bleu_score': 0.7791901449873281, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4531375377998650099}, 'section': 'Section::::Abstract.'}]}]