Dear Gurus,
How can I sort this Hash:

my %HoHoA = (
              'set1' => {
                         'AAAAAAA' => [ ['1','BOOK'],['2','PENCIL'] ],
                         'BBBBBBB' => [ ['0','CHALK'],['4','PEN'] ],
                       }, 
             # length of 2nd keys = 7 (all the same in 'set1')

              'set2' => {
                         'AAA' => [ ['1','BOOK'],['2','PENCIL'] ],
                         'BBB' => [ ['0','CHALK'],['4','PEN'] ],
                       }, 
             # length of 2nd keys = 7 (all the same in 'set2')

              'set3' => {
                         'AAA' => [ ['1','BOOK'],['2','PENCIL'] ],
                         'BBB' => [ ['0','CHALK'],['4','PEN'] ],
                       }, 
              # length of 2nd keys = 3 (all the same in 'set3')

              'set4' => {
                         'AAAA' => [ ['1','BOOK'],['2','PENCIL'] ],
                         'BBBB' => [ ['0','CHALK'],['4','PEN'] ],
                       }, 
              # length of 2nd keys = 4 (all the same in 'set4')
);
[download]

Based on the length of its second key.Namely: AAAAAAA (7),AAA(3),AAAA(4). In ascending way such that finally it simply prints:

set2  # Length 3
set3  # Length 3
set4  # Length 4
set1  # Length 7
[download]

I'm stuck with this:

foreach  my $set ( sort {#???}  keys %HoHoA )
{
    print "$set\n";
}
[download]

Also keeping in mind that I may not now "what is" the second key. Please help. Thanks a lot for your time.

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