Question: when did descendants of the sun start filming
[{'answer': 'June 12 , 2015', 'provenance': [{'wikipedia_id': '47429273', 'title': 'Descendants of the Sun', 'start_paragraph_id': 64, 'start_character': 3, 'end_paragraph_id': 64, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Production.\n'}]}, {'provenance': [{'wikipedia_id': '47429273', 'title': 'Descendants of the Sun', 'start_paragraph_id': 64, 'start_character': 0, 'end_paragraph_id': 64, 'end_character': 690, 'bleu_score': 0.983672097934538, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4259105590097461787}, 'section': 'Section::::Production.\n'}]}]