Question: when did canada become a member of the united nations
[{'answer': '1945', 'provenance': [{'wikipedia_id': '1406618', 'title': 'Canada and the United Nations', 'start_paragraph_id': 11, 'start_character': 297, 'end_paragraph_id': 11, 'end_character': 301, 'bleu_score': 1.0, 'section': 'Section::::National Film Board of Canada.\n'}]}]