What are some potential solutions for displaying the correct contents in the shopping cart when using the include function in PHP for an external shop?

Issue: When using the include function in PHP for an external shop, the shopping cart may not display the correct contents due to scope issues. One potential solution is to pass the necessary variables to the included file using the global keyword or by including the file within a function and passing the variables as arguments.

// Solution: Pass variables using the global keyword
$cart_contents = array('item1', 'item2', 'item3');
global $cart_contents;
include 'external_shop.php';

// Solution: Pass variables using a function
function display_shopping_cart($cart_contents) {
    include 'external_shop.php';
}
$cart_contents = array('item1', 'item2', 'item3');
display_shopping_cart($cart_contents);