I have a Unicode string in Python, and I would like to remove all the accents (diacritics).

I found on the web an elegant way to do this (in Java):

1. convert the Unicode string to its long normalized form (with a separate character for letters and diacritics)
2. remove all the characters whose Unicode type is "diacritic".

Do I need to install a library such as pyICU or is this possible with just the Python standard library? And what about python 3?

Important note: I would like to avoid code with an explicit mapping from accented characters to their non-accented counterpart.

How about this:

import unicodedata
def strip_accents(s):
   return ''.join(c for c in unicodedata.normalize('NFD', s)
                  if unicodedata.category(c) != 'Mn')

This works on greek letters, too:

>>> strip_accents(u"A \u00c0 \u0394 \u038E")
u'A A \u0394 \u03a5'
>>> 

The character category "Mn" stands for Nonspacing_Mark, which is similar to unicodedata.combining in MiniQuark's answer (I didn't think of unicodedata.combining, but it is probably the better solution, because it's more explicit).

And keep in mind, these manipulations may significantly alter the meaning of the text. Accents, Umlauts etc. are not "decoration".