Question: who wrote things ain't what they used to be
[{'answer': 'music by Mercer Ellington', 'provenance': [{'wikipedia_id': '9712482', 'title': "Things Ain't What They Used to Be", 'start_paragraph_id': 1, 'start_character': 65, 'end_paragraph_id': 1, 'end_character': 90, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'lyrics by Ted Persons', 'provenance': [{'wikipedia_id': '9712482', 'title': "Things Ain't What They Used to Be", 'start_paragraph_id': 1, 'start_character': 95, 'end_paragraph_id': 1, 'end_character': 116, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '9712482', 'title': "Things Ain't What They Used to Be", 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 116, 'bleu_score': 0.9146912192286941, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11673369136388241922}, 'section': 'Section::::Abstract.'}]}]