What official is Shangshu?

Shangshu is the title of a senior official. In the official system of Qing Dynasty, six ministers were called Shangshu. For example, Shang Shu of the Ministry of Justice is now the head of the Ministry of Justice, the Ministry of Public Security, the Supreme Court and the Supreme Procuratorate. Shangshuling, which began in the Qin Dynasty, was originally an official of a small government, in charge of documents and ministers' seals. When Emperor Wu of the Han Dynasty was appointed as a eunuch (also known as the secretariat order), he became the Han Dynasty. ...