[Python-Dev] Why does PEP 7/8 explicitly suggest 2 spaces after a period?

[Random832]

On Sun, May 22, 2016, at 11:15, Peter Ludemann via Python-Dev wrote:
> I just tried a re-flow in emacs (M-q or fill-paragraph) and it didn't
> change my single space to two (it also changed 3 spaces after a period
> to 2; and it preserved my hanging indents).

It won't change a single space to two, but it will add two spaces after
a sentence which was previously at the end of a line... and it *won't*
break a line after a dot followed by a single space (Vim isn't clever
enough for this second bit), preferring to break before the preceding
word instead.

A dot followed by a single space is *permitted* (hence why you observed
it didn't change it to two), it is simply assumed to represent something
other than the end of a sentence, such as an initial in a name.