Generic params are not passed correctly to QuerySet methods' return type

[mkurnikov]

[CASE custom_unannotated_manager_select_related_returns_proper_queryset]
from django.db import models
class MyManager(models.Manager):
    pass
class User(models.Model):
    objects = MyManager()

reveal_type(User.objects)  # E: Revealed type is 'main.MyManager[main.User]'
reveal_type(User.objects.select_related())  # E: Revealed type is 'django.db.models.query.QuerySet[main.User*, main.User*]'
[/CASE]