Ensure stubs packages are not installed

• No sqlalchemy stub packages is installed (both sqlalchemy-stubs and sqlalchemy2-stubs are not compatible with v2)

Verify if the api is typed

• The api is not in a module listed in #6810 so it should pass type checking

Describe the typing issue

When I have a variable that contain an union of model type (foo: type[ModelA | ModelB]) property type is interpreted by mypy as mapped_type instead of InstrumentedAttribute[mapped_type].

To Reproduce

from typing_extensions import reveal_type

from sqlalchemy.orm import DeclarativeBase, Mapped


class Foo(DeclarativeBase):
    foobar: Mapped[str]


class Bar(DeclarativeBase):
    foobar: Mapped[str]


def foo(attribute: InstrumentedAttribute[Any]) -> None:
    pass


union: type[Foo | Bar] = Foo
foo(union.foobar)

Error

main.py:21: error: Argument 1 to "foo" has incompatible type "str"; expected "InstrumentedAttribute[Any]"  [arg-type]

Versions

• OS: Ubuntu 20.04
• Python: 3.10.12 | 3.11.6 | 3.12.0
• SQLAlchemy: 2.0.22 | 2.0.23
• Type checker (eg: mypy 0.991, pyright 1.1.290, etc): mypy 1.7.1

Additional context

sqlalchemy and mypy are installed in venv

requirements.txt

SQLAlchemy==2.0.23
mypy==1.7.1

minimal example can be found here https://github.com/Fred-si/sqlalchemy_union_type_issue