Question: when did the buffalo bills became a team
[{'answer': '1960', 'provenance': [{'wikipedia_id': '9976342', 'title': 'History of the Buffalo Bills', 'start_paragraph_id': 1, 'start_character': 42, 'end_paragraph_id': 1, 'end_character': 46, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '9976342', 'title': 'History of the Buffalo Bills', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 451, 'bleu_score': 0.7927906400938841, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17448986828840950905}, 'section': 'Section::::Abstract.'}]}]