Question: when did apple introduce retina display on macbook pro
[{'answer': '2012', 'provenance': [{'wikipedia_id': '3677824', 'title': 'MacBook Pro', 'start_paragraph_id': 1, 'start_character': 288, 'end_paragraph_id': 1, 'end_character': 292, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '3677824', 'title': 'MacBook Pro', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 393, 'bleu_score': 0.551091009047022, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12288985989711278684}, 'section': 'Section::::Abstract.'}]}]