Missing $ on loop variable

##</code><code>##

my %lengths = (
    1 => {x => 1,
          y => 2,
          z => [1,2,3],
         },
    2 => {x => 2,
          y => 3,
          z => [2,3,4],
         },
    3 => {x => 4,
          y => 5,
          z => [5,6,7],
         },
);

for my $coord (keys %lengths) {
   for (@{$lengths{$coord}{z}}) {
      print "$_\n";
   }
}

##</code><code>##

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