Is there a perl module that allows inheritance like a compile-time modifiable symbol table?

subclasshash.pl

use strict;
use warnings;
use 5.010;

{
  package A;
	our $hash={1=>'i',2=>'j'};
}

{
	package B;
	use base 'A';
	our $hash = {%{$A::hash}};
	$hash->{2}='ii';
	$hash->{3}='iii';
}
use Data::Dumper;
$A::hash->{1}='I';
print Dumper $A::hash; # WANT: { '1' => 'I', '2' => 'j' };
print Dumper $B::hash; # WANT: { '1' => 'I', '2' => 'ii', '3' => 'iii'};