Who are the so-called' Peng Zu and Wu Xian' in Qu Yuan and Li He's poems?

Peng Zu's legendary immortal experienced Xia and Shang Dynasties, and died after more than 800 years. Wu Xian = Yin Shang wizard, also known for his longevity.

Peng Zu: According to legend, his name is Cuikeng, and he is the great-grandson of Zhuan Xu. He was born in the Xia Dynasty, and Yao sealed him in Pengdi. By the end of Yin Dynasty, he was 767 years old (over 800 years old). Yin Wang thought he was a doctor, asking questions about illness and not politics (see Biography of Immortals and Biography of Immortals). Zhuangzi Qiushui: "Isn't it sad that Peng Zu has a long-standing reputation?" The Theory of Everything: "Mo Shou died of his son, and Peng Zu died." Qu Yuan's Tian Wen: "What does Peng Keng care about, and how long does it take to live forever?" Wu Xian: Wu, Minister of Wu State, King of Shang Dynasty. According to legend, he invented the drum, used divination and astrology, so he was a fairy figure.