Question: when did the apple iphone 4 come out
[{'answer': 'June 24 , 2010', 'provenance': [{'wikipedia_id': '23501895', 'title': 'IPhone 4', 'start_paragraph_id': 21, 'start_character': 3, 'end_paragraph_id': 21, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::History.:Release.\n'}]}, {'provenance': [{'wikipedia_id': '23501895', 'title': 'IPhone 4', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 396, 'bleu_score': 0.866226661788252, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3703382656887371002}, 'section': 'Section::::Abstract.'}]}]