Question: who wrote the music for once more with feeling
[{'answer': 'Joss Whedon', 'provenance': [{'wikipedia_id': '251815', 'title': 'Once More, with Feeling (Buffy the Vampire Slayer)', 'start_paragraph_id': 1, 'start_character': 258, 'end_paragraph_id': 1, 'end_character': 269, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '251815', 'title': 'Once More, with Feeling (Buffy the Vampire Slayer)', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 1018, 'bleu_score': 0.9668954950326201, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6565310499878399551}, 'section': 'Section::::Abstract.'}]}]