title: Python way of printing: with 'format' or percent form?
body: <p>In Python there seem to be two different ways of generating formatted output:</p>
  
  <pre><code>user = "Alex"
  number = 38746
  print("%s asked %d questions on stackoverflow.com" % (user, number))
  print("{0} asked {1} questions on stackoverflow.com".format(user, number))
  </code></pre>
  
  <p>Is there one way to be preferred over the other? Are they equivalent, what is the difference? What form should be used, especially for Python3?</p>