Unicode literals that work in python 3 and 2

So I have a python script that I'd prefer worked on python 3.2 and 2.7 just for convenience.

Is there a way to have unicode literals that work in both? E.g.

#coding: utf-8
whatever = 'שלום'

The above code would require a unicode string in python 2.x (u'') and in python 3.x that little u causes a syntax error.

Edit - Since Python 3.3, the u'' literal works again, so the u() function isn't needed.

The best option is to make a method that creates unicode objects from string objects in Python 2, but leaves the string objects alone in Python 3 (as they are already unicode).

import sys
if sys.version < '3':
    import codecs
    def u(x):
        return codecs.unicode_escape_decode(x)[0]
else:
    def u(x):
        return x

You would then use it like so:

>>> print(u('\u00dcnic\u00f6de'))
Ünicöde
>>> print(u('\xdcnic\N{Latin Small Letter O with diaeresis}de'))
Ünicöde