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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 set_message(self, title, msg, typ, url=None):
 """ Sets user notification message. Args: title: Msg. title msg: Msg. text typ: Msg. type url: Additional URL (if exists) Returns: Message ID. """

        return self.user.send_notification(title=title,
                                           message=msg,
                                           typ=typ,
                                           url=url)