use warnings;
use strict;

use Data::Dumper;
use JSON;

my %data;

for (0..10){
    $data{$_} = $_ * 5;
}

my $json = encode_json \%data;

open my $wfh, '>', 'saved.json'
  or die "can't open the damned file for writing!: $!";

print $wfh $json;
close $wfh;

open my $fh, '<', 'saved.json'
  or die "can't open the damned file for reading!: $!";

my $perl_href;

{
    local $/;
    $perl_href = decode_json $json
}

print Dumper $perl_href;

##</code><code>##

$VAR1 = {
          '2' => 10,
          '3' => 15,
          '0' => 0,
          '8' => 40,
          '5' => 25,
          '1' => 5,
          '4' => 20,
          '10' => 50,
          '9' => 45,
          '6' => 30,
          '7' => 35
        };