Question: when does callie torres leave grey's anatomy
[{'answer': 'twelfth season finale', 'provenance': [{'wikipedia_id': '7687028', 'title': 'Callie Torres', 'start_paragraph_id': 24, 'start_character': 225, 'end_paragraph_id': 24, 'end_character': 246, 'bleu_score': 1.0, 'section': 'Section::::Development.:Characterization.\n'}]}, {'provenance': [{'wikipedia_id': '7687028', 'title': 'Callie Torres', 'start_paragraph_id': 24, 'start_character': 0, 'end_paragraph_id': 24, 'end_character': 542, 'bleu_score': 0.9802931511945101, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15205715586813475051}, 'section': 'Section::::Development.:Characterization.\n'}]}]