Question: when does ncis season 15 come out on dvd
[{'answer': 'August 21st , 2018'}, {'provenance': [{'wikipedia_id': '49947058', 'title': 'NCIS (season 15)', 'start_paragraph_id': 54, 'start_character': 0, 'end_paragraph_id': 54, 'end_character': 82, 'bleu_score': 0.7694297399066481, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10437292207953078993}, 'section': 'Section::::Home media.\n'}]}]