Azure AD Service Principal authentication to SQL DB - Code Sample

When we deployed the production, there is no client secret key anymore.  How will the example work without a client secret key?  Do we just leave that blank?

<Amol> This will not work without a secret key, how is your app getting a token, Once you have a token, you can directly put it here  and then connect. Token will start with something like ey....

conn.AccessToken = "<your token>";