Question: when did the shooting happen in greys anatomy
[{'answer': 'May 20 , 2010', 'provenance': [{'wikipedia_id': '47069325', 'title': "Death and All His Friends (Grey's Anatomy)", 'start_paragraph_id': 15, 'start_character': 120, 'end_paragraph_id': 15, 'end_character': 133, 'bleu_score': 1.0, 'section': 'Section::::Reception.:Broadcast.\n'}]}, {'answer': 'season finale of the sixth season'}, {'provenance': [{'wikipedia_id': '47069325', 'title': "Death and All His Friends (Grey's Anatomy)", 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 927, 'bleu_score': 0.9774114419330401, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4317246776964119814}, 'section': 'Section::::Abstract.'}]}]