code1 = state 1
code2 = state 2
...

##</code><code>##

use strict;
use Config::Tiny;

my $Config = Config::Tiny->read( 'ZipCodes.ini' );

sub check {
 my $code = shift;
 return $Config->{_}{$code} or die "No such code '$code' "; 
}

my $st_name = check ( $code ) ;