Start with this in a Repl (replit):

from os import getenv
print(getenv("REPLIT_DB_URL"))

Now that we have your db url, use this in your computer's IDE:

from os import environ
environ["REPLIT_DB_URL"] = "<INSERT YOUR DB URL FROM ABOVE HERE>"
from replit import db

You can now use it on your local machine with that file.

print(os.getenv("REPLIT_DATABASE_URL"))

use this and copy the url that is printed.
Afterwards, u just need to add this to the database:

from replit import db
db.db_url = "<...>"

**notes: ** Replit database was made specifically for replit, this is not an ideal solution, and there is no perfect solution.
For security, the database url is reset every once in a while, so you will have to update the url each time the url doesn't work anymore.