Question: when does season 16 of american idol end
[{'answer': 'May 21 , 2018', 'provenance': [{'wikipedia_id': '55948457', 'title': 'American Idol (season 16)', 'start_paragraph_id': 1, 'start_character': 341, 'end_paragraph_id': 1, 'end_character': 354, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '55948457', 'title': 'American Idol (season 16)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 529, 'bleu_score': 0.6044398771100541, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9793272244023620679}, 'section': 'Section::::Abstract.'}]}]