Add the error if the client could not connect to the server.

notification_client/client.py

@@ -19,6 +19,8 @@
 
 import asyncio
 import struct
+import sys
+
 from notification_client.MessagePrinter import MessagePrinter
 from notification_client.notitication import Notification
 
@@ -31,7 +33,12 @@ class Client:
         self.__port = port
 
     async def connect(self):
+        try:
             reader, writer = await asyncio.open_connection(self.__ip, self.__port)
+        except ConnectionRefusedError:
+            sys.stderr.write("Could not connect to the server. Please, check the ip and the port.\n")
+            sys.exit(1)
+
         await self.handle(reader, writer)
 
     @staticmethod