title: Pandas data-frame creation as permutations of 2 series?
body: <p>I have data set with two columns </p>
  
  <pre><code>ColA ColB
  1    1 
  2    2
  3    3
  </code></pre>
  
  <p>I want to create resultant frame of </p>
  
  <pre><code>ColA ColB
  1    1
  1    2
  1    3
  2    1
  2    2
  2    3
  3    1
  3    2
  3    3
  </code></pre>