title: Inserting the same value multiple times when formatting a string
body: <p>I have a string of this form</p>
  
  <pre><code>s='arbit'
  string='%s hello world %s hello world %s' %(s,s,s)
  </code></pre>
  
  <p>All the %s in string have the same value (i.e. s).
  Is there a better way of writing this? (Rather than listing out s three times)</p>