Trying to create generic CRUD class for all endpoints - python-3.x

Question

I am fairly new to FastAPI(migrating from Django) and I am trying to create a generic CRUD operations class that I can inherit and use across my CBV endpoints.
Something like this :
class AbstractCrud
model: Base = NotImplemented
session: Session = NotImplemented
def get_items(self, limit, **filters):
""" Read operation """
def get_item(self, pk: int):
def create_item(self, obj: BaseModel):
""" Create operation """
def update_item(self, pk: int, **params):
""" Update operation"""
def delete_item(self, pk: int):
""" Delete operation """
router = InferringRouter()
#cbv(router)
class UserAPI(AbstractCrud):
router.tags = ["User"]
router.prefix = "/users"
model = User
session: Session = Depends(get_db)
# my endpoints
#e.g. #router.get(...)
#cbv(router)
class PostAPI(AbstractCrud):
router.tags = ["Post"]
router.prefix = "/posts"
model = Post
session: Session = Depends(get_db)
# my endpoints
#e.g. #router.get(...)
I get the following error if I try to do the above:
fastapi.exceptions.FastAPIError: Invalid args for response field! Hint: check that <class 'sqlalchemy.orm.decl_api.Base'> is a valid pydantic field type
For now, I am able to achieve this as follows:
class AbstractCrud
model: Base = NotImplemented
session: Session = NotImplemented
def get_items(self, limit, **filters):
""" Read operation """
def get_item(self, pk: int):
def create_item(self, obj: BaseModel):
""" Create operation """
def update_item(self, pk: int, **params):
""" Update operation"""
def delete_item(self, pk: int):
""" Delete operation """
class UserCrud(AbstractCrud):
def __init__(self, session: Session):
self.session = session
self.model = User
class PostCrud(AbstractCrud):
def __init__(self, session: Session):
self.session = session
self.model = Post
router = InferringRouter()
#cbv(router)
class UserAPI:
router.tags = ["User"]
router.prefix = "/users"
def __init__(self, session=Depends(get_db)):
self.session = session
self.crud = UserCrud(self.session)
# my endpoints
#e.g. #router.get(...)
#cbv(router)
class PostAPI:
router.tags = ["Post"]
router.prefix = "/posts"
def __init__(self, session=Depends(get_db)):
self.session = session
self.crud = PostCrud(self.session)
# my endpoints
#e.g. #router.get(...)
Although this is working fine for me now, I can't help but think if there is a better(or correct) way to do this.
Also, Is my use of a single router variable across multiple classes correct?