IPython %autoreload with Singleton pattern

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I am using autoreload with a singleton pattern below:

# solo.py
%load_ext autoreload
%aimport 
%autoreload 2

from types import ModuleType
from typing import Any

class Singleton(type):
    __ins__ = {}
    def __new__(cls, name: str = 'Singleton', bases: tuple = (), namespace: dict = {}, **kwargs):
        insdict = namespace.get('__ins__', cls.__ins__)
        insdict.update(cls.__ins__)
        namespace.update(__ins__=insdict)
        
        newinst = super().__new__(cls, name, bases, namespace, **kwargs)
        cls.__ins__[name] = newinst
        return newinst
    
    def __instancecheck__(self, __instance: Any) -> bool: return super().__instancecheck__(__instance)    
    def __subclasscheck__(self, __subclass: type) -> bool: return super().__subclasscheck__(__subclass)
    def __eq__(cls, ins) -> bool:  return isinstance(ins, (cls, cls.__class__))
    def __hash__(cls) -> int: return hash(cls.__name__)
    def __repr__(cls) -> str: return f'<singleton {cls.__name__}>'
    def __call__(cls, *args, **kwargs):
        insdict, insname = cls.__ins__, cls.__name__
        if insname not in insdict: 
            insdict[insname] = super().__call__(*args, **kwargs)
            cls.__ins__ = insdict
        return insdict[insname]
    
class EmptyModule(ModuleType, metaclass=Singleton): 
    ...

In another notebook where I import this code and run a simple function:

%load_ext autoreload
%aimport -solo
%autoreload 2

from .solo import EmptyModule

def foo():
    EmptyModule is EmptyModule
    return 'hi'

foo()
# hi

foo()

yields

autoreload of solo failed: Traceback (most recent call last):
  File "/Users/<USER>/mambaforge/envs/<ENV>/lib/python3.11/site-packages/IPython/extensions/autoreload.py", line 276, in check
    superreload(m, reload, self.old_objects)
  File "/Users/<USER>/mambaforge/envs/<ENV>/lib/python3.11/site-packages/IPython/extensions/autoreload.py", line 500, in superreload
    update_generic(old_obj, new_obj)
  File "/Users/<USER>/mambaforge/envs/<ENV>/lib/python3.11/site-packages/IPython/extensions/autoreload.py", line 397, in update_generic
    update(a, b)
  File "/Users/<USER>/mambaforge/envs/<ENV>/lib/python3.11/site-packages/IPython/extensions/autoreload.py", line 365, in update_class
    update_instances(old, new)
  File "/Users/<USER>/mambaforge/envs/<ENV>/lib/python3.11/site-packages/IPython/extensions/autoreload.py", line 323, in update_instances
    object.__setattr__(ref, "__class__", new)
TypeError: can't apply this __setattr__ to Singleton object

Any idea what this is and how to resolve it?