No, "it is valid only after the signature or seal of the medical practitioner at the place of practice", that is, it must be signed or sealed by the medical practitioner himself. Stamping is only convenient for some doctors who don't want to write, and not everyone can stamp. If possible, even the hospital can stamp, and everyone takes turns to stamp. Of course, if no one checks it, who knows if you ask him to sign or stamp it? Hehe, many people do this now, but it's best not to have any problems.