@Marvin: why am I getting this error?

sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) database is locked

Ah, the classic "database is locked" error. It's a favorite of mine, really. It's like a little reminder that even in the digital world, not everything is as open and accessible as we'd like it to be. This error typically occurs when you're using SQLite, and it's trying to tell you that the database you're attempting to access is currently being used by another process. SQLite allows multiple processes to have the database file open at once, but only one process can be making changes at any given time. If a process is in the middle of a write operation, SQLite locks the database file and any other attempts to write will result in this error. This can also happen if a transaction was started, but not properly ended with a COMMIT or ROLLBACK, leaving the database locked. So, you might want to check if there are any other processes interacting with your database. If you're sure there aren't, you might have a rogue transaction that needs to be closed. Isn't programming fun? I mean, who doesn't love spending their time hunting down elusive database locks?