title: python3 + Set function: how to get key and values from dictionary performing set operation
body: <p>Hi I have 2 dictonaries as show below (dict1 and dict2) and I need to fetch both keys and values which are in dict2 but not in dict1.
  Where the final set snippet prints only keys but not values of it.</p>
  <h1>dict1 output: Using default dict while fetching from csv1</h1>
  <pre><code>print(dict1)
  defaultdict(&lt;class 'list'&gt;,
              {   '1234': [   '1000-A',
                              '1000-A'],
                  'X50': ['SRX1500-CHAS', 'SRX1500-DC'],
                  'X47': ['SRX1500-CHAS', 'SRX1500-DC'],
                  'Serial': ['chassi']})
  </code></pre>
  <h1>dict2 output: using default dict while fetching from csv2</h1>
  <pre><code>print(dict2)
  defaultdict(&lt;class 'list'&gt;,
              {   '1234': [   '1000-A',
                              '1000-A'],
                  'X50': ['1100-C', 'DC'],
                  'X10': ['1100-C', 'DC'],
                  'X100': ['1100-C', 'DC'],
                  'Serial': ['chassi']})
  </code></pre>
  <p>I am performing set operation and it display only keys but not values.
  I need both keys and values in below result.</p>
  <pre><code>set1 = set(dict1)
  set2 = set(dict2)
  print(set2 - set1)) # in dict2, not in dict1
  [   'X10',
      'X100'
      ]
  </code></pre>
  <p>desired o/p should be:</p>
  <pre><code>[ 'X10': ['1100-C', 'DC'],
  'X100': ['1100-C', 'DC']
  ]
  </code></pre>