As_manager: Self not taken into account

[moranabadie]

Bug report

from django.db import models
from typing_extensions import Self
class MyQuerySet(BaseQuerySet):
       def example_simple(self) -> Self: ...

class MyModel(models.Model):
     objects = MyQuerySet.as_manager()
reveal_type(MyModel.objects.example_simple())  # -> Revealed type is "<nothing>" 

What's wrong

The issue lies in the type revelation within the custom QuerySet method that is supposed to return Self. Currently, it reveals the type as <nothing>, which indicates that the Self type isn't properly recognized or handled.

How is that should be

The correct and expected behavior should reveal the type accurately, as per the following expectation:

reveal_type(MyModel.objects.example_simple())  # -> Revealed type is "myapp.models.ManagerFromMyQuerySet[myapp.models.MyModel]"

System information

• OS:
• python 3.12
• django 3.2.12
• mypy 1.6.1
• django-stubs 4.2.5
• django-stubs-ext 4.2.5

[sobolevn]

PR is welcome.