[Question] How to integrate sendgrid API into Lemmy Ansible installation?

I’m using the Lemmy ansible installation method. I’ve been trying to add sendgrid to the postfix section of the config.hjson file on my local machine. But where do I add the API key and username? I used port 587 but nothing works. Can anyone help walk me through how to integrate sendgrid into Lemmy-Ansible? Thanks!!...