Question: who was the leader of great britain during wwii
[{'answer': 'Winston Churchill', 'provenance': [{'wikipedia_id': '10040664', 'title': 'Allied leaders of World War II', 'start_paragraph_id': 17, 'start_character': 490, 'end_paragraph_id': 17, 'end_character': 507, 'bleu_score': 1.0, 'section': 'Section::::British Empire and Commonwealth.\n'}]}]