/**
  * Saves tax-profile to the invoice.
  *
  * @since  1.0.0
  * @param  MS_Model_Invoice $invoice The invoice object.
  * @return MS_Model_Invoice
  */
 public function invoice_tax_profile($invoice)
 {
     $invoice->set_custom_data('tax_profile', MS_Addon_Taxamo_Api::get_tax_profile());
     return $invoice;
 }