Interestingly, you know who else spotted the error? ChatGPT-4o. Annoyingly you can't share a chat with an image in it, but pasting in the image of the bad code, and prompting "whats wrong with the code" got ChatGPT to tell me that:

* UUID Generation in Primary Key: The default parameter should use the callable uuid.uuid4 directly instead of str(uuid.uuid4()). SQLAlchemy will call the function to generate the value.

* Date Default Value: server_default=text("(now())") might not work as expected. Use func.now() for server-side defaults in SQLAlchemy.

* Import Statements: Ensure uuid and text from sqlalchemy are imported.

* Column Definitions: Consider using DateTime(timezone=True) for datetime columns to handle time zones.

It then provided me with corrected code that does

    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()), unique=True, nullable=False)

where the addition of lambda: fixes the problem.