package p1;

my $var1 = 'var1-p1';

sub new {
    my $class = ref $_[0] ? ref shift : shift;
    my $self = {};
    bless $self, $class;
    return $self;
}

sub get_var1 {
	return $var1;
}

1;

##</code><code>##

package p2;

use p1;

our @ISA=qw(p1);

sub set_var1 {
	my $self = shift;
	my $new_var1 = shift;
	$var1 = $new_var1;
	return $var1;
}

1;

##</code><code>##

use p2;

my $obj = p2->new();
say $obj->get_var1() . "\n";
say $obj->set_var1('changed') . "\n";
say $obj->get_var1() . "\n"

##</code><code>##

var-p1
changed
changed