def __init__(self, index):
    self.index = index

@property
def uniqueid(self):
    return 'foo'


class Player(game.Player, Base):
    __tablename__ = 'player'
id = Column(Integer, primary_key=True)
_uniqueid = Column('uniqueid', String(21), unique=True, nullable=False)

def __init__(self, index, **kwargs):
    pass
Override a read-only property with a read-only Column that gets the same value