How to edit Kali Linux Repositories/Sources (apt sources.list) using Gedit or Leafpad

How many times have you messed-up your Kali Linux repositories/sources list? How many times you forgot how to edit the list using a text editor (available in Kali Linux)? It happened a lot of times to me so, I'll just keep this as a note for myself. My repositories list contains only two lines of text. In case you've changed it and need to get it back to the…