title: Python 2's `exceptions` module is missing in Python3, where did its contents go?
body: <p>A friend mentioned that with Python 2, (assuming you have it on your path environment variable, on the commandline) </p>
  
  <pre><code>$ pydoc exceptions 
  </code></pre>
  
  <p>is very useful and knowing it should save him a few minutes of web lookup time a week. I Google the exceptions hierarchy about once a week myself, so this was a helpful reminder for me as well. It is the same documentation that you get with </p>
  
  <pre><code>&gt;&gt;&gt; import exceptions
  &gt;&gt;&gt; help(exceptions) 
  </code></pre>
  
  <p>in Python 2, because <code>pydoc</code> uses the exceptions module to provide the online documentation.</p>
  
  <p>However, he noted this doesn't work with Python 3. This is because the <code>exceptions</code> module doesn't exist in Python 3.</p>
  
  <p>I can see why he likes it - it shows the very useful exceptions hierarchy for quick perusal, and I reference it myself frequently. But the <code>exceptions</code> module with the resulting builtin documentation is missing from Python 3! How can he replace it?</p>
  
  <p>To ensure that Stackoverflow has the answer to this question, in general: </p>
  
  <blockquote>
    <p><strong>How does one replace the contents of the exceptions module in Python 2 when moving to Python 3?</strong></p>
  </blockquote>