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$ date -u +'%F %T %s %z'
2011-08-16 06:42:12 1313476932 +0000
$ python -c 'import sys, datetime; now = datetime.datetime.utcnow(); sys.stdout.write(now.strftime("%F %T %s %z"))'
2011-08-16 06:42:12 1313440932
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The documentation for ‘datetime.datetime.utcnow’ says “Return a new datetime representing UTC day and time.” The resulting object should be in the UTC timezone, not a naive no-timezone value.
This results in programs specifically requesting UTC time with ‘utcnow’, but then Python treating the return value as representing local time since it is not marked with the UTC timezone.