RefExpr in determining model fullname not supported

test-data/typecheck/migrations.test

@@ -8,6 +8,23 @@ model_cls = apps.get_model('myapp', 'User')
 reveal_type(model_cls)  # E: Revealed type is 'Type[myapp.models.User]'
 reveal_type(model_cls.objects)  # E: Revealed type is 'django.db.models.manager.Manager[myapp.models.User]'
 
+[file myapp/__init__.py]
+[file myapp/models.py]
+from django.db import models
+class User(models.Model):
+    pass
+
+[CASE registry_apps_get_model_passed_as_variables_not_supported]
+from django.apps.registry import Apps
+from typing import TYPE_CHECKING
+if TYPE_CHECKING:
+    from myapp.models import User
+app_name = 'myapp'
+model_name = 'User'
+apps = Apps()
+model_cls = apps.get_model(app_name, model_name)
+reveal_type(model_cls)  # E: Revealed type is 'Type[django.db.models.base.Model]'
+
 [file myapp/__init__.py]
 [file myapp/models.py]
 from django.db import models
@@ -28,4 +45,4 @@ reveal_type(model_cls.objects)  # E: Revealed type is 'django.db.models.manager.
 [file myapp/models.py]
 from django.db import models
 class User(models.Model):
-    pass
+    pass