Fix string comparisons on port mode

"is not" doesn't work here. :-(

Change-Id: I6e9db2ab64a7b7468a705bc6a534a9ada209bd95

1 files changed, 2 insertions, 2 deletions

diff --git a/util.py b/util.py
index 42a8bc0..463b91d 100644
--- a/util.py
+++ b/util.py
@@ -426,8 +426,8 @@ class VlanUtil:
         config = state.config
 
         # 1. Sanity-check inputs
-        if mode is not 'access' and mode is not 'trunk':
-            raise InputError("Port mode %s is not a valid option: try 'access' or 'trunk" % mode)
+        if mode != 'access' and mode != 'trunk':
+            raise InputError("Port mode '%s' is not a valid option: try 'access' or 'trunk'" % mode)
         port = db.get_port_by_id(port_id)
         if port is None:
             raise InputError("Port ID %d does not exist" % port_id)