Only add a single instance of LogHandlerSumo to the logger returned by SumoClient.getLogger.

Author: rwiker

src/sumo/wrapper/sumo_client.py

@@ -383,8 +383,10 @@ def getLogger(self, name):
         """
 
         logger = logging.getLogger(name)
-        handler = LogHandlerSumo(self)
-        logger.addHandler(handler)
+        if len(logger.handlers) == 0:
+            handler = LogHandlerSumo(self)
+            logger.addHandler(handler)
+            pass
         return logger
 
     @raise_for_status_async