is prisma python client official?

It is not, however it is built on the official Prisma Engine and the project is sponsored by prisma.

is it okay to use it as production level?

It is unstable, and some features may be missing or incomplete. I would recommend reading up on it at https://prisma-client-py.readthedocs.io/en/stable/.

As William mentioned, only the JavaScript/TypeScript client is official. Other clients like Python and Rust are community maintained and not official.