title: How to split string before number
body: <p>I have a string <code>1 blahblahblah 2 sdsdsdsdsd 3 uuuuuu 4 eeee 5 abcdef</code>
  I would like to output</p>
  
  <pre><code>1 blahblahblah
  2 sdsdsdsdsd
  3 uuuuuu
  4 eeee
  5 abcdef
  </code></pre>
  
  <p>I have tried to add <code>\n</code> before every number by using <code>re.split</code> but it didn't work</p>
  
  <pre><code>re.split(' (?=[1-9]:)', line)
  </code></pre>