patch for Python 2.6 by him.
iCalendar 2.0.1 (2008-07-11)
============================
API Changes:
* EXDATE and RDATE now returns a vDDDLists object, which contains a list
of vDDDTypes objects. This is do that EXDATE and RDATE can contain
lists of dates, as per RFC.
***Note!***: This change is incompatible with earlier behavior, so if you
handle EXDATE and RDATE you will need to update your code.
* When createing a vDuration of -5 hours (which in itself is nonsensical),
the ical output of that was -P1DT19H, which is correct, but ugly. Now
it's '-PT5H', which is prettier.
* Made the tests run under Python 2.5+
* Renamed the UTC class to Utc, so it would not clash with the UTC object,
since that rendered the UTC object unpicklable.
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