14.11.17 22:34, Ivan Levkivskyi пише:

This function will be called only if ``name`` is not found in the module
through the normal attribute lookup.

It is worth to mention that using name as a module global will bypass __getattr__. And this is intentional, otherwise calling __getattr__ for builtins will harm a performance.

Backwards compatibility and impact on performance
=================================================

What is affect on pydoc, word completion, inspect, pkgutil, unittest?

   def keep_pickleable(func):
       func.__name__ = func.__name__.replace('_deprecated_', '')
       func.__qualname__ = func.__qualname__.replace('_deprecated_', '')
       return func

   @keep_pickleable
   def _deprecated_old_function(arg, other):
       ...

I would create more standard helpers (for deprecation, for lazy importing). This feature is helpful not by itself, but because it will be used for implementing new features. Using __getattr__ directly will need to write a boilerplate code. Maybe when implementing these helper you will discover that this PEP needs some additions.