title: Unique items in cart
body: <p>I want every product to appear as single cart items.</p>
  
  <p>So instead of changing the quality of a product it must appear as a unique cart items</p>
  
  <p>I thought this was possible by making the $cart_id unique, but unfortunately this doesn't work.</p>
  
  <p>What must I add to my functions.php file to create a unique cart item?</p>
  
  <p>Thanks in advance....</p>