String performance regression from python 3.2 to 3.3

[jmfauth]

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utf-32 is already here. You are all most probably [*]
using it without noticing it. How? By using OpenType fonts,
without counting the text processing applications using them.
Why? Because there is no other way to do it.

[*] depending of the font, the internal table(s), eg "cmap" table,
are in utf-16 or utf-32.

jmf