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#!/usr/bin/perl --
use strict;
use warnings;
use Data::Dump qw/ dd /;
my %hash = ( 1,2 );
my $ref = \%hash;
dd( $ref );
$ref->{alec}='smart';
dd( $ref );
__END__
{ 1 => 2 }
{ 1 => 2, alec => "smart" }
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