title: Pandas multiple column intersection
body: <p>I have a data frame as follows:</p>
  
  <pre><code>data={'NAME':['JOHN','MARY','CHARLIE'],
    'A':[[1,2,3],[2,3,4],[3,4,5]],
    'B':[[2,3,4],[3,4,5],[4,5,6]],
      'C':[[2,4],[3,4],[6,7]]  }
  df=pd.DataFrame(data)
  df=df[['NAME','A','B','C']]
  NAME          A          B            C
  0   JOHN    [1, 2, 3]   [2, 3, 4]   [2, 4]
  1   MARY    [2, 3, 4]   [3, 4, 5]   [3, 4]
  2   CHARLIE [3, 4, 5]   [4, 5, 6]   [6, 7]
  </code></pre>
  
  <p>I need intersection of all columns A, B, C.</p>
  
  <p>I tried following code but did not work:</p>
  
  <pre><code>df['D']=list(set(df['A'])&amp;set(df['B'])&amp;set(df['C']))
  </code></pre>
  
  <p>The output required is as follows:</p>
  
  <pre><code>    NAME            A         B         C       D
  0   JOHN    [1, 2, 3]   [2, 3, 4]   [2, 4]  [2]
  1   MARY    [2, 3, 4]   [3, 4, 5]   [3, 4]  [3, 4]
  2   CHARLIE [3, 4, 5]   [4, 5, 6]   [6, 7]  []
  </code></pre>