Question: when were the lascaux caves closed to the public
[{'answer': '1963', 'provenance': [{'wikipedia_id': '18594', 'title': 'Lascaux', 'start_paragraph_id': 4, 'start_character': 411, 'end_paragraph_id': 4, 'end_character': 415, 'bleu_score': 1.0, 'section': 'Section::::History since rediscovery.\n'}]}]