'%r' docs

[Pearu Peterson]

Hi!

To my pleasing surprice I discovered (from some python code, not
mine) that '%s'%(repr(obj)) has shorter form '%r'%(obj).

Though I scanned Python 2.1 docs in order to find some backing for this
discovery, I found non.
 
So, is this undocumented feature (and therefore may disappear in
future??)? Or could some one point out where are the fancy output formats
documented beside in the Tutorial.

Thanks,
	Pearu