How to deploy multiple Django apps (as subdomains) using nginx and Gunicorn

I have a new 18.04 Droplet running a Django website on nginx. I’d like to use this droplet to serve several websites at subdomains. I have successfully:

1. Followed this excellent tutorial to set up my first website: https://www.digitalocean.com/community/tutorials/how-to-set-up-django-with-postgres-nginx-and-gunicorn-on-ubuntu-18-04

2. Configured nginx and DNS to serve (static) websites & subdomains on this server

3. Set up a second Django app that I can run on port 8000, using Gunicorn as a console process

So where I’m hung up is what I add to the systemd configuration? I tried copy/pasting the [Service] block for my new site but when I try to restart gunicorn I get this error:

systemd[1]: gunicorn.service: Service has more than one ExecStart= setting, which is only allowed for Type=one

Should I create a second *.service file in /etc/systemd/system/? Is there some way to put multiple Django apps into one ExecStart directive? Each app runs in its own virtual environment.