Why does this (very simple piece of) code does not work?

[Richard Brodie]

"jblazi" <jblazi at hotmail.com> wrote in message news:pan.2004.08.16.13.03.51.421000 at hotmail.com...

>        y = 'Kapustin (Hamelin): '+x
>        os.rename(x,y)
> OSError: [Errno 22] Invalid argument

You didn't say what platform you are on but if it's Windows, then
colons aren't allowed in filenames.