metaclass and new style generics do not work.

Bug Report
mypy fails with (modern and old) generics and metaclass, the whole application crashes.

To Reproduce
create a class like:

class AbstractModelMeta(ABCMeta, type(models.Model)):
    """
    A Django model and Python abstract class
    https://gist.github.com/gavinwahl/7778717
    """

    pass

class SomeClass[TAttachment: Something](models.Model, metaclass=AbstractModelMeta):
    @abstractmethod
    def send_something(self) -> None:
        """
        Send a notification to the original sender of a classification record that their classification record
        has or has not been processed in AP Automation
        """
        pass

The traceback is:

https://mypy.readthedocs.io/en/stable/common_issues.html#using-a-development-mypy-build
Please report a bug at https://github.com/python/mypy/issues
version: 2.3.0
Traceback (most recent call last):
  File "<frozen runpy>", line 203, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "mypy/semanal.py", line 7732, in accept
  File "mypy/nodes.py", line 1165, in accept
  File "mypy/semanal.py", line 991, in visit_func_def
    self.analyze_func_def(defn)
  File "mypy/semanal.py", line 1036, in analyze_func_def
    self.defer(defn)
  File "mypy/semanal.py", line 7333, in defer
    assert not self.final_iteration, "Must not defer during final iteration"
AssertionError: Must not defer during final iteration

src/isp/invoice/classification/models/base/base_classification_record.py:31: note: use --pdb to drop into pdb

Expected Behavior

I expect mypy to correctly understand this. or at least not choke on this.

Actual Behavior

This reports a failure:

error: INTERNAL ERROR -- Please try using mypy master on GitHub:
https://mypy.readthedocs.io/en/stable/common_issues.html#using-a-development-mypy-build

Your Environment

• Mypy version used: 2.3
• Mypy command-line flags:
• Mypy configuration options from mypy.ini (and other config files): from toml file:

[tool.mypy]
python_version = "3.12"
plugins = ["mypy_django_plugin.main"]
ignore_missing_imports = true
exclude = ["migrations/", "130192/", "000000/", "130344/"]
mypy_path = "src"

[tool.django-stubs]
django_settings_module = "isp.platform.conf.dev"

• Python version used: 3.14.6

I also tried to tell mypy to ignore this file, but when I add it to the "exclude" everything that refers this breaks. And if I try to ignore it any other way it seems to constantly report this error. Is there a way to tell mypy to ignore a file, and manually say "hey this type should be considered "Any".

Reproduce the crash with the shown generic Django model, metaclass, mypy 2.3 configuration, and traceback. Start in mypy/semanal.py around analyze_func_def and defer, then follow the visitor path from mypy/nodes.py. Done means the example no longer raises an internal error and mypy reports a usable result for the class.