$ perl -wMstrict -MDateTime -le 'print DateTime->now(time_zone=>$_)->strftime("%Z %z") for qw# America/Havana Asia/Shanghai America/Chicago #'
CST -0500
CST +0800
CST -0600

##</code><code>##

$ perl -wMstrict -MDateTime -le 'print DateTime->new(year=>$_,time_zone=>"Pacific/Apia")->strftime("%Y %z") for qw/ 2010 2012 /'
2010 -1100
2012 +1400