title: What is the point of re-raising exceptions?
body: <p>So I've seen mention elsewhere of using the following to re-raise an exception.</p>
  
  <pre><code>try:
      whatever()
  except:
      raise
  </code></pre>
  
  <p>What is the purpose re-raising an exception? Surely an uncaught exception will just raise to the top anyway? i.e:</p>
  
  <pre><code>try:
      int("bad")
  except:
      raise
  </code></pre>
  
  <p>has identical output to:</p>
  
  <pre><code>int("bad")
  </code></pre>
  
  <p>i.e. I get a ValueError in the console.</p>