$VAR1 = {
  'Intersection' => [
    '4',
    '5'
  ],
  'Sym_diff' => [
    '1',
    '2',
    '3',
    '6',
    '7',
    '8'
  ],
  'Difference' => [
    '1',
    '2',
    '3'
  ],
  'Union' => [
    '1',
    '2',
    '3',
    '4',
    '5',
    '6',
    '7',
    '8'
  ]
};