// Specify an invoice ID to get a QR code (image) that corresponds to the invoice ID. A QR code for an invoice can be added to a paper or PDF invoice. When a customer uses their mobile device to scan the QR code, the customer is redirected to the PayPal mobile payment flow, where they can pay online with PayPal or a credit card.
/** @var Invoice $invoice */
$invoice=require'SendInvoice.php';
usePayPal\Api\Invoice;
usePayPal\Api\Notification;
try{
// ### Retrieve QR Code of Sent Invoice
// Retrieve QR Code of Sent Invoice by calling the