Question: when is the releasing date of avengers infinity war
[{'answer': 'April 27 , 2018', 'provenance': [{'wikipedia_id': '44240443', 'title': 'Avengers: Infinity War', 'start_paragraph_id': 57, 'start_character': 262, 'end_paragraph_id': 57, 'end_character': 277, 'bleu_score': 1.0, 'section': 'Section::::Release.:Theatrical.\n'}]}]