Update shipment with carrier for a given tracking number

- Added a check to print a message if the shipment does not exist and the update flag is set
- Added an error message for cases where a shipment cannot be created because it does not exist

src/trackbert/__main__.py

@@ -140,6 +140,11 @@ def main():
             print(
                 f"Updated shipment for {args.tracking_number} with carrier {args.carrier}"
             )
+
+        if shipment is None and args.update:
+            print(f"Shipment {args.tracking_number} does not exist. Remove -u to create.")
+            exit(1)
+
         else:
             tracker.db.create_shipment(
                 args.tracking_number, args.carrier, args.description

src/trackbert/config.dist.ini

@@ -12,4 +12,4 @@ secret = api_secret
 [DHL]
 key = api_key
 secret = api_secret
-ratelimited = 1
+ratelimited = 1