Giant panda Mao Zhu enjoys a special cake made for its 4thbirthday celebration at Yunnan Wildlife Zoo in Kunming City, Southwest China’s Yunnan Province, July 26, 2018. (Photo: China News Service/Liu Ranyang)

Giant panda Mao Zhu enjoys a special cake made for its 4thbirthday celebration at Yunnan Wildlife Zoo in Kunming City, Southwest China’s Yunnan Province, July 26, 2018. (Photo: China News Service/Liu Ranyang)

Giant panda Mao Zhu enjoys a special cake made for its 4thbirthday celebration at Yunnan Wildlife Zoo in Kunming City, Southwest China’s Yunnan Province, July 26, 2018. (Photo: China News Service/Liu Ranyang)

Giant panda Mao Zhu enjoys a special cake made for its 4thbirthday celebration at Yunnan Wildlife Zoo in Kunming City, Southwest China’s Yunnan Province, July 26, 2018. (Photo: China News Service/Liu Ranyang)

Giant panda Mao Zhu enjoys a special cake made for its 4thbirthday celebration at Yunnan Wildlife Zoo in Kunming City, Southwest China’s Yunnan Province, July 26, 2018. (Photo: China News Service/Liu Ranyang)