Question: when does transformers the dark knight come out
[{'answer': 'June 21 , 2017', 'provenance': [{'wikipedia_id': '44422168', 'title': 'Transformers: The Last Knight', 'start_paragraph_id': 78, 'start_character': 48, 'end_paragraph_id': 78, 'end_character': 62, 'bleu_score': 1.0, 'section': 'Section::::Release.\n'}]}]