SqlAlchemy postgres bulk upsert

sample.py

from sqlalchemy.dialects import postgresql

def bulk_upsert(session: Session, 
                items: Sequence[Mapping[str, Any]]):
  session.execute(
    postgresql.insert(MyModel.__table__)
    .values(items)
    .on_conflict_do_update(
      index_elements=[MyModel.id],
      set_={MyModel.my_field.name: 'new_value'},
    )
  )

Made my day!

Is there a way to pass to set_ in on_conflict_do_update a list of values from items, instead of a default value for all the records being upserted?

Following works a bit better:

  session.execute(
    postgresql.insert(MyModel.__table__)
    .values(items)
    .on_conflict_do_update(
      index_elements=MyModel.__table__.primary_key.columns,
      set_=items
    )
  )

Actually the correction does not seem to be working
ValueError: set parameter must be a non-empty dictionary or a ColumnCollection such as the .c. collection of a Table object
the items have to be dict, can't have a Sequence[Mapping] as in here