title: itertools 'previous' (opposite of next) python
body: <p>I'm currently using something like </p>
  
  <pre><code>&gt;&gt; import itertools
  &gt;&gt; ABC = [a, b, c]
  &gt;&gt; abc = itertools.cycle( ABC )
  &gt;&gt; next( abc )
  a
  &gt;&gt; next( abc )
  b    
  &gt;&gt; next( abc )
  c
  </code></pre>
  
  <p>I want my next call to be</p>
  
  <pre><code>&gt;&gt; previous( abc )
  b
  </code></pre>
  
  <p>Is there a method in itertools that can accomplish this?</p>