from sqlalchemy import select
from sqlalchemy import ForeignKey, String
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column


class Base(DeclarativeBase):
     pass

class User(Base):
     __tablename__ = "user_account"

     id: Mapped[int] = mapped_column(primary_key=True)
     address_id: Mapped[int] = mapped_column(ForeignKey("address.id"))
     model_type: Mapped[str] = mapped_column(String(50))
     __mapper_args__ = {"polymorphic_identity": "base", "polymorphic_on": "model_type"}


class Admin(User):
     __mapper_args__ = {"polymorphic_identity": "admin"}

class Address(Base):
     __tablename__ = "address"
     id: Mapped[int] = mapped_column(primary_key=True)

print(select(Address.id).select_from(Admin).join(Address))