Generic TypeVar solution for class that produces another class that contains the original class

I’m trying to come up with a generic TypeVar solution to avoid having to create an ever expanding Uniontype annotation. Here’s a somewhat contrived MRE of what I have currently:

from __future__ import annotations

from typing import Union


class CreatedDetails:

    def __init__(self, creator: Union[Creator1, Creator2], new: bool) -> None:
        self.creator = creator
        self.new = new


class Creator1:

    def __init__(self) -> None:
        self.name = "creator1"

    def create(self) -> CreatedDetails:
        return CreatedDetails(creator=self, new=True)


class Creator2:

    def __init__(self) -> None:
        self.name = "creator2"

    def create(self) -> CreatedDetails:
        return CreatedDetails(creator=self, new=False)


creator1 = Creator1()

created = creator1.create()

created.creator.name

This plays nice and my type checker recognises everything:

However, this relies on me adding new Creator classes to the Ùnion type annotation.

I’ve tried using a generic TypeVar:

from __future__ import annotations

from typing import TypeVar

CreatorRecord = TypeVar("CreatorRecord")


class CreatedDetails:

    def __init__(self, creator: CreatorRecord, new: bool) -> None:
        self.creator = creator
        self.new = new


class Creator:
    pass


class Creator1(Creator):

    def __init__(self) -> None:
        self.foo = "foo"

    def create(self) -> CreatedDetails:
        return CreatedDetails(creator=self, new=True)


class Creator2(Creator):

    def __init__(self) -> None:
        self.bar = "bar"

    def create(self) -> CreatedDetails:
        return CreatedDetails(creator=self, new=False)


creator1 = Creator1()

created = creator1.create()

created.creator.foo
created.new

However, the type checker doesn’t fully recognise this:

Where am I going wrong?

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