class Base(DeclarativeBase):
    pass

class User(Base):
    __tablename__ = "users"
    __table_args__ = {"schema": "app"}

    # Not a real column - just here to satisfy SQLAlchemy's requirement for a primary key for every table
    id: Mapped[int] = orm.mapped_column(
        BigInteger, primary_key=True, autoincrement=True
    )

    email: Mapped[Optional[str]] = orm.mapped_column(String)

engine = create_engine("bigquery://", echo=True)
Base.metadata.create_all(engine)

row = User(email="my@email.com")

with Session(engine) as session:
    with session.begin():
        session.add(row)