Question: when did north and south korea go to war
[{'answer': '25 June 1950', 'provenance': [{'wikipedia_id': '16772', 'title': 'Korean War', 'start_paragraph_id': 1, 'start_character': 95, 'end_paragraph_id': 1, 'end_character': 107, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '16772', 'title': 'Korean War', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 410, 'bleu_score': 0.527809983748705, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16839097448738618112}, 'section': 'Section::::Abstract.'}]}]