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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 notify_deleted(room, event, user, room_deleted):
 """Notifies about the deletion of a chatroom. :param room: the chatroom :param event: the event :param user: the user performing the action; `None` if due to event deletion :param room_deleted: if the room has been deleted from the jabber server """

    tpl = get_plugin_template_module('emails/deleted.txt', chatroom=room, event=event, user=user,
                                     room_deleted=room_deleted)
    _send(event, tpl)