[sqlalchemy] Creating column SQLAlchemy property on parent class based on child column property

The structure I have created is like below:     class Parent(Base):        __tablename__ = 'parent'            id = Field(            Integer,            primary_key=True        )            type_ = Field(            String(50),            readonly=True        )            __mapper_args__ = { 

[sqlalchemy] Get sqlalchemy base class object instead of children

Hi everybody,I have three classes in my model, which one class inherited by the other two:     class Item(Base):        __tablename__ = 'item'         id = Column(Integer, primary_key=True)        title = Column(Unicode(300))        type = Column(Unicode(50))         __mapper_args__ = {