Type inference fails for foreign keys with custom app names

[aleksanb]

If you have a foreign key or similar that refers to a model with a string, and you have a custom app name for the app where that model lives, the inferred type falls back to Any:

class UserConfig(AppConfig):
    name = 'hyre.user'
    label = 'hyre__user'

if TYPE_CHECKING:
    from hyre.user.models import User

class MyClass(models.Model):
    some_fk = models.ForeignKey( 'hyre__user.User', ...)

mypy-django will look for the model User in a file called hyre__user, but only hyre.user exists in all_modules in helpers.py.