Question: when did the us and the uk become allies
[{'answer': '1940', 'provenance': [{'wikipedia_id': '1814362', 'title': 'United Kingdom–United States relations', 'start_paragraph_id': 1, 'start_character': 304, 'end_paragraph_id': 1, 'end_character': 308, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1814362', 'title': 'United Kingdom–United States relations', 'start_paragraph_id': 1, 'start_character': 133, 'end_paragraph_id': 1, 'end_character': 421, 'bleu_score': 0.7523634340221501, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9685364734311196906}, 'section': 'Section::::Abstract.'}]}]