use strict;
use warnings;

my $obj = bless {global1 => 0, global2 => 3};

$obj->setThree (6);
$obj->doSomething ();
print $obj->{four};


sub setThree {
    my ($self, $three) = @_;
    $self->{three} = $three;
}


sub doSomething {
    my ($self) = @_;
    $self->{four} = $self->{three} + $self->{global2};
}

##</code><code>##

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