use warnings;
use strict;
use DateTime;
use DateTime::Format::Strptime;

my $fmt = '%d %b %Y %T %z';

my $strp = DateTime::Format::Strptime->new( on_error=>'croak',
	pattern=>$fmt );

my $dt = DateTime->now;
$dt->set_time_zone('America/Chicago');  # try this with "%Z"...
print $dt->rfc3339, "\n";
my $str = $dt->strftime($fmt);
print "$str\n";
my $dt2 = $strp->parse_datetime($str);
print $dt2->rfc3339, "\n";