[docs] platform.python_implementation() miswording

[Corey Richardson]

On Sun, 27 May 2012 21:44:48 +0200
Sandro Tosi <sandro.tosi at gmail.com> <sandro.tosi at gmail.com> wrote:
>
> I'm a non-native speaker, so can you please explain why your proposed
> version is better than the actual one? 
> 

The reason it is better is because there could be other
implementations not accounted for in the docs, and it would be silly to
have *every* possible implementation string. The first implies, to me,
that the list includes all possible values, which is simply false

> Also your phrase contains a typo: Python -> CPython.
> 

Ah yes, my bad, it should read CPython.

-- 
Corey Richardson