diff --git a/test/js-example.js b/test/js-example.js
index f1329e6..bef470e 100644
--- a/test/js-example.js
+++ b/test/js-example.js
@@ -165,3 +165,23 @@ function extractEvents(
   }
 }
 
+
+function mark_purchased(transaction) {
+    transaction.state = TransactionState.PURCHASED
+    for (item in transaction.items) {
+        if (item.mtb_product_ids) {
+        if (item.mtb_product_ids) {
+            for (mp_id in item.mtb_product_ids) {
+                try {
+                    mtb_prod = get_db_mtb_product(None, mp_id, all=True, refresh=False)
+                    mtb_prod.purchased = True
+                    mtb_prod.save()
+                }
+                catch(exc) {
+                    logger.error("Failed to mark mtb_product {mp_id} as purchase", exc_info=exc)
+                }
+            }
+        }
+        }
+    }
+  }
\ No newline at end of file