Question: when did the league of nations ceased to function as a viable organization
[{'answer': '18 April 1946', 'provenance': [{'wikipedia_id': '17926', 'title': 'League of Nations', 'start_paragraph_id': 133, 'start_character': 57, 'end_paragraph_id': 133, 'end_character': 70, 'bleu_score': 1.0, 'section': 'Section::::Demise and legacy.\n'}]}, {'provenance': [{'wikipedia_id': '17926', 'title': 'League of Nations', 'start_paragraph_id': 133, 'start_character': 0, 'end_paragraph_id': 133, 'end_character': 477, 'bleu_score': 0.941591348007749, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7887743730465004518}, 'section': 'Section::::Demise and legacy.\n'}]}]