[Python] Why am I getting "Class 'sqlalchemy.engine.row.Row' is not mapped" when trying to...

I've just moved from SQLAlchemy 1.3 to 1.4 and am trying out the new 2.0 syntax. Given the following table:

class Player(Base):

__table_args__ = {"schema": "test"}
__tablename__ = "player"

id_ = sa.Column(sa.Integer, primary_key=True)
name_ = sa.Column(sa.String(100))


I add some records:

dal.session.add_all([Player(1, "t1"), Player(2, "t2"), Player(3, "t3")])


I can delete records using 1.x:

del_records = session.query(Player).filter(Player.id_ <= 10)
for d in del_records:
session.delete(d)


However, when I switch to 2.0:

del_records = session.execute(sa.select(Player).where(Player.id_ <= 10))
for d in del_records:
session.delete(d)


I get the following error:

Exception has occurred: UnmappedInstanceError (note: full exception trace is shown but execution is paused at: <module>)
Class 'sqlalchemy.engine.row.Row' is not mapped

The above exception was the direct cause of the following exception:

File "/Users/philipjoss/Documents/GitHub/polgara/sandpit.py", line 61, in <module> (Current frame)
dal.session.delete(d)


Any idea what's going on?

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