Cannot use Connection.transaction() in a manually started transaction

[Kigstn]

Heya all,

I'm having a problem with asyncpg and sqlalchemy (both latest), where sometimes, my query will fail with:
sqlalchemy.dialects.postgresql.asyncpg.AsyncAdapt_asyncpg_dbapi.InterfaceError: <class 'asyncpg.exceptions._base.InterfaceError'>: cannot use Connection.transaction() in a manually started transaction

I have searched far and wide and have not found out what this error actually means nor a way to reliably reproduce it. It just happens eventually. I was hoping someone could help me clear up why this happens and how to prevent it. I assume this is the relevant code which throws the error.

I sadly do not have any code to reliably reproduce this issue, here is a stack trace tho. All errors produce the same stack trace.