title: How to split a Python string with numbers and letters?
body: <p>I have strings that have optional numbers and letters, such as '01a', 'b' and '02'. These strings have always two parts, numbers on the left, and letters on the right side. I'd like to split these strings to get the numbers and letters separately. How can I define <code>mySplit</code> in a way to get this result?</p>
  
  <pre><code>&gt;&gt;&gt; map(mySplit, ['01123absd', 'bsdf', '02454'])
  
  [('01123', 'absd'), (None, 'bsdf'), ('02454', None)]
  </code></pre>