Question: when does descendants 2 come on on disney channel
[{'answer': 'July 21 , 2017', 'provenance': [{'wikipedia_id': '50444775', 'title': 'Descendants 2', 'start_paragraph_id': 42, 'start_character': 220, 'end_paragraph_id': 42, 'end_character': 234, 'bleu_score': 1.0, 'section': 'Section::::Soundtrack.\n'}]}, {'provenance': [{'wikipedia_id': '50444775', 'title': 'Descendants 2', 'start_paragraph_id': 1, 'start_character': 78, 'end_paragraph_id': 1, 'end_character': 462, 'bleu_score': 0.830404420869007, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 961737881433096294}, 'section': 'Section::::Abstract.'}]}]