title: Insert values to a pandas column containing list alternatively from other column containing list
body: <p>Posting minimal reproducible example</p>
  <p>Lets say I have a dataframe</p>
  <pre><code>            combined              values
  0    [0, 0, 0, 0, 0, 0, 0, 0]     [1, 2, 3, 4]
  1    [0, 0, 0, 0, 0, 0, 0, 0]     [5, 6, 7, 8] 
  2             [0, 0, 0, 0, 0]     [9, 10, 11]
  </code></pre>
  <p>Now I need to populate column <code>combined</code> from column <code>values</code> such that, it is populated alternatively, like :</p>
  <pre><code>            combined              values
  0    [1, 0, 2, 0, 3, 0, 4, 0]     [1, 2, 3, 4]
  1    [5, 0, 6, 0, 7, 0, 8, 0]     [5, 6, 7, 8] 
  2           [9, 0, 10, 0, 11]     [9, 10, 11]
  </code></pre>
  <p>It is guranteed that size of lists in <code>combined</code> will always be atleast 2 times the size of list in <code>values</code>.</p>
  <p>I am looking for a solution more of slicing and inserting the values to the list, but that wouldn't work</p>
  <pre><code>df['combined'].str[::2] = df['values'].str[::]
  </code></pre>
  <p><strong>P.S :</strong> There are numerous ways in which this can be achieved I am looking for a more <code>pandaic</code> approach</p>