title: At a dataframe how to explode a column with a list (with same length at all rows) into different columns at the same row
body: <p>I have following dataframe:</p>
  
  <pre><code>df=pd.DataFrame({'A': ['1','2', '3'], 'List': [['a1','a2'], ['b1','b2'], ['c1','c2']]})
  
  Out[18]: 
     A      List
  0  1  [a1, a2]
  1  2  [b1, b2]
  2  3  [c1, c2]
  </code></pre>
  
  <p>I would like to explode the column <em>List</em> into two new columns (<em>L1</em> and <em>L2</em>) at the same row.</p>
  
  <pre><code>   A  L1  L2
  0  1  a1  a2
  1  2  b1  b2
  2  3  c1  c2
  </code></pre>
  
  <p>Which would be the fastest way to do it?</p>
  
  <p>It would be great to assign also the names for the columns at the same time (L1 and L2).</p>
  
  <p>Thank you in advance and best regards,</p>
  
  <p>Pablo G</p>