title: How to add a string in a certain position?
body: <p>Is there any function in Python that I can use to insert a value in a certain position of a string?</p>
  
  <p>Something like this:</p>
  
  <p><code>"3655879ACB6"</code> then in position 4 add <code>"-"</code> to become <code>"3655-879ACB6"</code></p>