title: Check letters in the string
body: <p>How to check if the first three letters in the string are the same as three last letters reversed. They can't overlap. 
  For example: </p>
  
  <pre><code>"karak" -&gt; False
  "kaakaak" -&gt; True
  </code></pre>
  
  <p>Figured out that like this I can check out first three and last three reversed letters of string:</p>
  
  <pre><code>if s[:3] == s[-3:][::-1]:
  </code></pre>
  
  <p>But how to check if they are overlaping or not?</p>