Who invented glutinous rice balls?

During the period of Emperor Wu of the Han Dynasty, there was a maid-in-waiting named Yuanxiao.

Yuanxiao in the palace misses her parents and sisters very much and often cries alone in the boudoir. This homesickness deeply touched Dong Fangshuo. So Dong Fangshuo made up the story that the Jade Emperor wanted to "burn Chang 'an" and asked the Emperor Wu of the Han Dynasty to approve every household to make glutinous rice balls and light lanterns on the 15th day of the first month. Meanwhile, the maids were allowed to leave the palace. On the fifteenth day of the first month, the maid-in-waiting Yuanxiao went out of the palace with a lantern with the word "Yuanxiao" written on it, and finally reunited with her family and enjoyed the family happiness she dreamed of. Since then, jiaozi has been called Yuanxiao!