Question: who wrote the music in west side story
[{'answer': 'Leonard Bernstein', 'provenance': [{'wikipedia_id': '33928', 'title': 'West Side Story', 'start_paragraph_id': 1, 'start_character': 68, 'end_paragraph_id': 1, 'end_character': 85, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '33928', 'title': 'West Side Story', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 181, 'bleu_score': 0.6176324097551581, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14403700163168682040}, 'section': 'Section::::Abstract.'}]}]