from typing import List
from sqlalchemy import Column
from sqlalchemy import ForeignKey
from sqlalchemy import Integer
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship
Base = declarative_base()
class B(Base):
__tablename__ = "b"
id = Column(Integer, primary_key=True)
as_: List["A"] = relationship("A", collection_class=None)
another_as_ = relationship("A", uselist=True)
class A(Base):
__tablename__ = "a"
id = Column(Integer, primary_key=True)
b_id: int = Column(ForeignKey("b.id"))
b: B = relationship(B, uselist=False, collection_class=set)