Please ride the donkey backwards, thank you!

It is a familiar story that Zhang rode backwards on a donkey. In history, Zhang did exist. It is said that he was an alchemist in the Tang Dynasty. He often rides a white donkey between Fenzhou and Jinzhou in Shanxi. His white donkey can travel thousands of miles every day. When you don't need it, you can fold it up and put it in the suitcase. Just water it when you ride. Because of his reputation, both Emperor Taizong and Emperor Gaozong called him, but neither of them went. Tang Xuanzong even planned to marry Princess Yu Zhen to him, but he also refused. When Wu Zetian summoned him, Zhang died in front of a temple, and the body rotted quickly, so Wu Zetian had to give up. But then someone saw him in Zhongtiaoshan.