Question: when was the apple ipad mini 4 released
[{'answer': 'September 9 , 2015', 'provenance': [{'wikipedia_id': '47768517', 'title': 'IPad Mini 4', 'start_paragraph_id': 3, 'start_character': 75, 'end_paragraph_id': 3, 'end_character': 93, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '47768517', 'title': 'IPad Mini 4', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 365, 'bleu_score': 0.675168979853705, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17917294571208151372}, 'section': 'Section::::Abstract.'}]}]