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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def guess_message_type(message):
 """ Guess the message type based on the class of message :param message: Message to guess the type for :type message: APPMessage :return: The corresponding message type (MsgType) or None if not found :rtype: None | int """

    if isinstance(message, APPConfigMessage):
        return MsgType.CONFIG
    elif isinstance(message, APPJoinMessage):
        return MsgType.JOIN
    elif isinstance(message, APPDataMessage):
        # All inheriting from this first !!
        return MsgType.DATA
    elif isinstance(message, APPUpdateMessage):
        return MsgType.UPDATE
    elif isinstance(message, APPUnjoinMessage):
        return MsgType.UNJOIN
    # APPMessage -> ACK?
    return None