title: Python increment string with both letters and numbers
body: <p>I am attempting to increment a string that has both letters and numbers in it - each of the characters in the string can either be 0-9 or a-z, no upper case letters.</p>
  
  <p>Ideally I would hope it could be incremented in a +1 fashion in the sense that if the string was o6 to o7 o8 o9 oa ob etc to oz then p0 p1 etc <em>by the way that's a lower base O not a zero</em></p>
  
  <p>The method I use to increment only works by converting string to int, then incrementing by +1 and cannot be used here.</p>
  
  <pre><code>number = str(int(number) + 1)
  </code></pre>