diff --git a/req_delivery.py b/req_delivery.py
index e985f98..1140dc4 100644
--- a/req_delivery.py
+++ b/req_delivery.py
@@ -132,5 +132,8 @@ def req_delivery(address_file='default_address.json'):
         })))
     
 if __name__ == '__main__':
-    req_delivery(sys.argv[1])
+    if len(sys.argv) == 1:
+        req_delivery()
+    else:
+        req_delivery(sys.argv[1])