Question: when did the true story of unstoppable happen
[{'answer': '2001', 'provenance': [{'wikipedia_id': '29609451', 'title': 'CSX 8888 incident', 'start_paragraph_id': 1, 'start_character': 162, 'end_paragraph_id': 1, 'end_character': 166, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '29609451', 'title': 'CSX 8888 incident', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 443, 'bleu_score': 0.7746256398408811, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 501527990583308895}, 'section': 'Section::::Abstract.'}]}]