Question: when was the last time usa hosted winter olympics
[{'answer': '2002', 'provenance': [{'wikipedia_id': '34069', 'title': 'Winter Olympic Games', 'start_paragraph_id': 4, 'start_character': 167, 'end_paragraph_id': 4, 'end_character': 171, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '34069', 'title': 'Winter Olympic Games', 'start_paragraph_id': 4, 'start_character': 11, 'end_paragraph_id': 4, 'end_character': 855, 'bleu_score': 0.699405892894548, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8946398925132033919}, 'section': 'Section::::Abstract.'}]}]