Question: who led the soviet union at the beginning of the cold war
[{'answer': 'Truman', 'provenance': [{'wikipedia_id': '325329', 'title': 'Cold War', 'start_paragraph_id': 1, 'start_character': 427, 'end_paragraph_id': 1, 'end_character': 433, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]