title: Reverse a string in Python
body: <p>There is no built in <code>reverse</code> function for Python's <code>str</code> object. What is the best way of implementing this method?</p>
  
  <p>If supplying a very concise answer, please elaborate on its efficiency. For example, whether the <code>str</code> object is converted to a different object, etc. </p>