This was obtained through physical examination. It is to get a health certificate for the catering industry. You go to your local physical examination center and say I want to get a health certificate, and they will tell you what to do. In fact, it is to have a blood test and do some simple physical examinations. After that, I will give you a proof. The catering industry cannot have diseases such as hepatitis A, hepatitis B and hepatitis B carriers! So if there is, the physical examination will not pass.