Consider this little Python script: import dateutil.parser import pytz
x = dateutil.parser.parse("2013-08-16 23:00:00+01:00") localtz = pytz.timezone("America/Chicago") y = localtz.normalize(x) When I execute it (Python 2.7.2, dateutil 1.5, pytz 2011h), I get this traceback: Traceback (most recent call last): File "/home/skipm/tmp/localtzex.py", line 8, in <module> y = localtz.normalize(x) File "/opt/TWWfsw/python27p/lib/python2.7/site-packages/pytz/tzinfo.py", line 233, in normalize offset = dt.tzinfo._utcoffset AttributeError: 'tzoffset' object has no attribute '_utcoffset' Looking at the tzinfo attribute, I see that it has "utcoffset", but not "_utcoffset". I realize those are the latest, most up-to-datest versions of all three elements. I'm having trouble updating dateutil and pytz on my Mac at home (stuck on even older versions). Can someone with newer versions of dateutil and pytz see if this problem is still present? Thx, Skip -- http://mail.python.org/mailman/listinfo/python-list