The autocomplete can suggest results from a remote API - objects that do not exist in the local database.
This project demonstrates how test_remote_project can provide autocomplete suggestions using the database from test_project.
In one console:
cd test_project ./manage.py runserver
cd test_remote_project ./manage.py runserver 127.0.0.1:8001
Now, note that there are no or few countries in test_api_project database.
Then, connect to http://localhost:8001/admin/remote_autocomplete/address/add/ and the city autocomplete should propose cities from both projects.
If you're not going to use localhost:8000 for test_project, then you should update source urls in test_remote_project/remote_autocomplete/autocomplete_light_registry.py.