perl -MData::Dumper -le 'my %oddcubes = map { $_%2 ? ($_ => $_**3) : () } 1..9; print Dumper \%oddcubes'
$VAR1 = {
          '1' => 1,
          '3' => 27,
          '7' => 343,
          '9' => 729,
          '5' => 125
        };