Question: when was the us involved in the korean war
[{'answer': '1945', 'provenance': [{'wikipedia_id': '39332124', 'title': 'United States in the Korean War', 'start_paragraph_id': 1, 'start_character': 187, 'end_paragraph_id': 1, 'end_character': 191, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '39332124', 'title': 'United States in the Korean War', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1663, 'bleu_score': 0.992740351871881, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12300026741103864725}, 'section': 'Section::::Abstract.'}]}]