Question: who composed the music for la la land
[{'answer': 'Justin Hurwitz', 'provenance': [{'wikipedia_id': '47204682', 'title': 'La La Land (film)', 'start_paragraph_id': 2, 'start_character': 108, 'end_paragraph_id': 2, 'end_character': 122, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]