Question: what was the city of beijing previously known as
[{'answer': 'Peking', 'provenance': [{'wikipedia_id': '18603746', 'title': 'Beijing', 'start_paragraph_id': 1, 'start_character': 56, 'end_paragraph_id': 1, 'end_character': 62, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18603746', 'title': 'Beijing', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 596, 'bleu_score': 0.8102227332886741, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15186120485658787474}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18603746', 'title': 'Beijing', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 1034, 'bleu_score': 0.9879148529393721, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15186120485658787474}, 'section': 'Section::::Etymology.\n'}]}, {'provenance': [{'wikipedia_id': '23587', 'title': 'Peking (disambiguation)', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ["Peking usually refers to Beijing, the capital city of the People's Republic of China.", "Peking usually refers to Beijing, the capital city of the People's Republic of China", "Peking usually refers to Beijing, the capital city of the People's Republic of China"]}}]}, {'provenance': [{'wikipedia_id': '18603746', 'title': 'Beijing', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ["Beijing ( , nonstandard ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China, the world's third most populous city proper, and most populous capital city.", "Beijing ( , nonstandard ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China, the world's third most populous city proper, and most populous capital city.", 'Beijing ( , nonstandard ; ), alternatively romanized as Peking']}}]}, {'provenance': [{'wikipedia_id': '291328', 'title': 'Beijing Capital International Airport', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ["The airport's IATA Airport code, PEK, is based on the city's former romanized name, Peking.", "The airport's IATA Airport code, PEK, is based on the city's former romanized name, Peking. Beijing Capital has rapidly ascended in rankings of the world's busiest airports in the past decade."]}}]}]