That depends on how the hash was stored.

You could use Storable to freeze/thaw the hash like this:

use strict;
use warnings;
use Storable qw(freeze thaw);
use Data::Dumper;

my %orig = ( 1 => 2, a => 'b');
my $frozen = freeze(\%orig);
print "Frozen: $frozen\n";

my $restored = thaw($frozen);
print "Thawed: ", Dumper $restored;
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Or you could be lazy (and insecure) and use Data::Dumper and eval like this:

use strict;
use warnings;
use Data::Dumper;
$Data::Dumper::Purity = 1;
$Data::Dumper::Terse = 1;

my %orig = ( 1 => 2, a => 'b');
my $frozen = Dumper(\%orig);
print "Frozen: $frozen\n";

my $restored = eval $frozen;
print "Thawed: ", Dumper $restored;
print "Error: $@\n";
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