Question: what body of water borders japans west coast
[{'answer': 'Sea of Japan', 'provenance': [{'wikipedia_id': '15575', 'title': 'Geography of Japan', 'start_paragraph_id': 2, 'start_character': 600, 'end_paragraph_id': 2, 'end_character': 612, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]