lazy_import.py

import importlib
import inspect

class LazyImport:
    def __init__(self, module):
        self._module = module

    def __getattr__(self, name):
        try:
            value = getattr(self._module, name)
            if inspect.ismodule(value):
                return LazyImport(value)
            return value
        except AttributeError:
            pass
        try:
            return LazyImport(importlib.import_module(self._module.__name__ + "." + name))
        except ImportError:
            raise AttributeError(f"module '{self._module.__name__}' has no attribute '{name}'") from None


# in win32more/__init__.py
# lazy = LazyImport(sys.modules[__name__])
# then
# from win32more import lazy as win32more
# win32more.Windows.Win32.UI.WindowsAndMessaging.MessageBox(...)