title: Print all items in a list with a delimiter
body: <p>Consider this Python code for printing a list of comma separated values</p>
  <pre><code>for element in list:
      print element + &quot;,&quot;,
  </code></pre>
  <p>What is the preferred method for printing such that a comma does not appear if <code>element</code> is the final element in the list.</p>
  <p>ex</p>
  <pre><code>a = [1, 2, 3]
  for element in a
    print str(element) +&quot;,&quot;,
  
  output
  1,2,3,
  desired
  1,2,3
  </code></pre>