Question: when did les mis open in the west end
[{'answer': 'October 1985', 'provenance': [{'wikipedia_id': '237789', 'title': 'Les Misérables (musical)', 'start_paragraph_id': 1, 'start_character': 497, 'end_paragraph_id': 1, 'end_character': 509, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]