title: Splitting a column of strings and counting the number of words with pandas
body: <pre><code>id   string   
  0    31672;0           
  1    31965;0
  2    0;78464
  3      51462
  4    31931;0
  </code></pre>
  
  <p>Hi, I have that table. i would like to split the string table by the ';', and store it to the new column. the final column shold be like this</p>
  
  <pre><code> id   string   word_count
  0    31672;0    2       
  1    31965;0    2
  2    0;78464    2
  3      51462    1
  4    31931;0    2
  </code></pre>
  
  <p>it would be nice if someone knows how to do it with python.</p>