title: Zip lists in Python
body: <p>I am trying to learn how to "zip" lists. To this end, I have a program, where at a particular point, I do the following:</p>
  
  <pre><code>x1, x2, x3 = stuff.calculations(withdataa)
  </code></pre>
  
  <p>This gives me three lists, <code>x1</code>, <code>x2</code>, and <code>x3</code>, each of, say, size 20.</p>
  
  <p>Now, I do:</p>
  
  <pre><code>zipall = zip(x1, x2, x3)
  </code></pre>
  
  <p>However, when I do:</p>
  
  <pre><code>print "len of zipall %s" % len(zipall)
  </code></pre>
  
  <p>I get 20, which is not what I expected. I expected three. I think I am doing something fundamentally wrong.</p>