Question: when was the first portable mp3 player released
[{'answer': '1997', 'provenance': [{'wikipedia_id': '1560437', 'title': 'Portable media player', 'start_paragraph_id': 9, 'start_character': 143, 'end_paragraph_id': 9, 'end_character': 147, 'bleu_score': 1.0, 'section': 'Section::::History.:AT&T FlashPAC.\n'}]}, {'provenance': [{'wikipedia_id': '1560437', 'title': 'Portable media player', 'start_paragraph_id': 11, 'start_character': 0, 'end_paragraph_id': 11, 'end_character': 446, 'bleu_score': 0.9748377259086851, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17975804839047641900}, 'section': 'Section::::History.:SaeHan/Eiger MPMan.\n'}]}]