Oh, the pull request is far larger than I thought!

I doubt that avoiding functools and collections is worth enough, because it is very common.

For example:

* functools is very commonly imported, especially for wraps().

* collections is imported by functools, so it's more commonly imported than functools.

* Old style namespace package (.pth file) imports types module, and types module and types imports functools, collections.  So even `python -c 42` imports them if at least one old-style namespace package is installed.  (e.g. Sphinx)


Instead of avoiding them, I want to make them faster.

* C implementation of ABC will makes collection, weakref and some other modules much faster.
* Recent PEP will allows split functools module into submodules without breaking backward compatibility.