Simplified Access to Namespaces in OOP in PHP

Suppose we have the following class Controller:

/admin/controller.php<?php
  namespace Admin;
  
  class Controller
  {
    
  }
?>

Suppose there is also a class Page that inherits from the class Controller:

/admin/page.php<?php
  namespace Admin;
  
  class Page extends \Admin\Controller
  {
    
  }
?>

As you can see, when inheriting, we specify the parent's name along with the namespace. In this example, however, there is a nuance: both classes belong to the same namespace. In this case, when referring to a class, you can simply write the name of that class, like this:

/admin/page.php<?php
  namespace Admin;
  
  class Page extends Controller
  {
    
  }
?>

php<?php
  namespace Modules\Shop;
  
  class Cart
  {
    
  }
?>

php<?php
  namespace Modules\Shop;
  
  class UserCart extends \Modules\Shop\Cart
  {
    
  }
?>