title: Trim string from left and from right
body: <p>How can I trim 5 characters from a string from left and right side. e.g.</p>
  
  <pre><code>4k2l3k4jc9l3kancie9
  </code></pre>
  
  <p>What should be trimmed and kept are:</p>
  
  <pre><code>4k2l3      k4jc9l3ka     ncie9
    ^            ^           ^
  remove        keep       remove
  </code></pre>