How to Override a Package's __init__.py Without Breaking Submodule Imports in Python?

I'm working on a project where I need to override files located in the ./lib/python3.9/site-packages" directory. I have the following hook that does just that using importlib.util and sys.meta_path.insert:

• The Override files is in ./lib_changes/*.

• The Hook does work in all of the following files except the zope+intid.__init__.py file

import reimport sysimport importlib.utilimport osfrom Zope2.Startup.serve import mainimport loggingLOGGER = logging.getLogger("RunWSGI")def generate_override_mapping(lib_changes_dir):    override_mapping = {}    for filename in os.listdir(lib_changes_dir):        if filename.endswith(".py"):            module_name = filename[:-3].replace("+", ".")            # Special handling for __init__.py files            if module_name.endswith(".__init__"):                module_name = module_name[:-9]            override_mapping[module_name] = os.path.join(lib_changes_dir, filename)    return override_mappingclass CustomImportHook:    def __init__(self, override_mapping):        self.override_mapping = override_mapping        self.override_counter = 0    def find_spec(self, fullname, path=None, target=None):        if fullname in self.override_mapping:            override_path = self.override_mapping[fullname]            LOGGER.info(f"{fullname} Overide by {override_path}")            self.override_counter += 1            return importlib.util.spec_from_file_location(fullname, override_path)        return Nonelib_changes_dir = '/opt/projects/Plone/site/backend/lib_changes'override_mapping = generate_override_mapping(lib_changes_dir)sys.meta_path.insert(0, CustomImportHook(override_mapping))if __name__ == '__main__':    sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])    sys.exit(main())

Problem: I'm trying to override zope.intid.__init__.py (or any .__init__.py file) with a custom implementation located in a different directory. However, I'm encountering an issue where the package submodules are not recognized correctly, leading to ModuleNotFoundError errors. For example, once the Hook successfully replaced the implementation of zope.intid.__init__.py with the one located at ./lib_changes, improts such as import zope.intid.interfaces is not longer working (err: ModuleNotFoundError: No module named 'zope.intid.interfaces'; 'zope.intid' is not a package.

Question: How can I properly override the __init__.py of the zope.intid package (or any .__init__.py package file) without breaking the import of its submodules? Is there a way to correctly set up the custom import hook to handle this scenario?