title: How one can unsource .sh format files?
body: <p>Suppose that I have sourced a bunch of .sh files via a single file as</p>
  
  <blockquote>
    <p>source .bash_profile</p>
  </blockquote>
  
  <p>Now, I want to use another installation. How can I un-source them before sourcing other .sh files? Is it even possible?</p>