The current os.path.isabs documentation says:

> isabs(path) 
>    Return True if path is an absolute pathname (begins with a slash). 

The "begins with a slash" part is incorrect since certain systems use a
different pathname notation.
For example, on Macintosh (where os.sep == ":") this is an absolute
pathname:

hardDriveName:folderName1:folderName2:fileName.ext

...and this is a relative one:

:folderName1:fileName.ext


Moreover, on Windows os.path.isabs('\\') returns True since '\\' is an
alias for the current drive letter (e.g. C:\\) hence, independently from
what said before, the documentation should include also the "backslash"
term.
I think it would be better removing the "(begins with a slash)" part at all.