Update mqtt_publish_subscribe.py

Scripts/core/mqtt_publish_subscribe.py

-import csv
-import logging
-import time
+import csv,logging,time
 
 
 class Mqtt_Publish:
@@ -33,7 +31,7 @@ class Mqtt_Publish:
                     list_kva.append({"Timestamp": row["Timestamp"], "Value": row['kVA']})
                     list_current.append({"Timestamp": row["Timestamp"], "Value": row['current']})
         except Exception :
-            logging.exception("Exception occurred in connection", exc_info=True)
+            logging.exception("Exception occurred in opening of file", exc_info=True)
         client.loop_start()
         if choice == "kwh":
             client.subscribe("Kwh")