Greasy Fork镜像

For learning Korean in English questioning what are the codes? For like the "Chinese=zs" and " Japanese=ja" what is the codes for "English=?" and "Korean=?"

To find language codes:

• start a lesson with your language in the browser
• the code is written in your url

Hey, it seems like when I go to a lesson, the url is just something like "https://www.duolingo.com/lesson/unit/16/level/4". I am doing a Spanish course. If you could give me the code or tell me how to, it would be great. Thanks!