title: How can I get the next string, in alphanumeric ordering, in Python?
body: <p>I need a simple program that given a string, returns to me the next one in the alphanumeric ordering (or just the alphabetic ordering).</p>
  
  <pre><code>f("aaa")="aab"
  f("aaZ")="aba"
  </code></pre>
  
  <p>And so on.</p>
  
  <p>Is there a function for this in one of the modules already?</p>