Update can/listener.py

Co-authored-by: zariiii9003 <52598363+zariiii9003@users.noreply.github.com>

Author: barbacbd

can/listener.py

@@ -112,7 +112,7 @@ def get_message(self, timeout: float = 0.5) -> Optional[Message]:
         :meth:`can.BufferedReader.stop` has been called.
 
         :param timeout: The number of seconds to wait for a new message.
-        :return: the Message if one exists, otherwise None.
+        :return: the received :class:`can.Message` or `None`, if the queue is empty.
         """
         try:
             if self.is_stopped: