Question: when did the attack on fort sumter happen
[{'answer': 'April 12 , 1861', 'provenance': [{'wikipedia_id': '81464', 'title': 'Fort Sumter', 'start_paragraph_id': 11, 'start_character': 11, 'end_paragraph_id': 11, 'end_character': 26, 'bleu_score': 1.0, 'section': 'Section::::Civil War.:First Battle of Fort Sumter.\n'}]}, {'provenance': [{'wikipedia_id': '81464', 'title': 'Fort Sumter', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 626, 'bleu_score': 0.9817332376369081, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6421444039404015634}, 'section': 'Section::::Abstract.'}]}]