title: How to create a multilevel dataframe in pandas?
body: <p>Given two different df's:</p>
  
  <p>'A'</p>
  
  <pre><code>            a  b         
  2016-11-21  2  1
  2016-11-22  3  4
  2016-11-23  5  2 
  2016-11-24  6  3 
  2016-11-25  6  3
  </code></pre>
  
  <p>'B'</p>
  
  <pre><code>            a  b         
  2016-11-21  3  0
  2016-11-22  1  0
  2016-11-23  1  6 
  2016-11-24  1  5 
  2016-11-25  0  2
  </code></pre>
  
  <p>How can I create a 'multilevel' dataframe of this shape:</p>
  
  <p>'C'</p>
  
  <pre><code>            A     B
              a  b  a  b           
  2016-11-21  2  1  3  0
  2016-11-22  3  4  1  0
  2016-11-23  5  2  1  6
  2016-11-24  6  3  1  5
  2016-11-25  6  3  0  2
  </code></pre>
  
  <p>*index is a 'datatime' object</p>
  
  <p>Thanks</p>