timezone argument %z and %Z

[Chris Angelico]

On Sat, Aug 16, 2014 at 6:21 PM, Ian Kelly <ian.g.kelly at gmail.com> wrote:
> You should also be aware that the abbreviations do not always uniquely
> identify a time zone. For example, "EST" is used in both North America
> (-0500) and Australia (+1000). It's usually better just to use time zone
> offsets to avoid this sort of ambiguity.

And about fifty other time zones, too. Offsets are great if you want
that simplicity, but the only reliable way to handle time zones with
DST changes is a tzdata identifier like "Australia/Adelaide" or
"America/New_York" (which correspond to the two meanings of EST that
you mentioned).

ChrisA