use Tie::Hash::Array;

tie my %hash, 'Tie::Hash::Array';

foreach(a..z){
    tie my %tmp, 'Tie::Hash::Array';
    my $t = $_;
    foreach my $i(0..5){
        $t++;
        $tmp{$t} = $i;
    }
    $hash{$_} = \%tmp;
}

use Data::Dumper;
print Dumper \%hash;

untie %hash;
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