def METHOD_NAME(self, root_topic):
    """Set the root topic for this handler.
    This value is prepended to all messages published by this handler, and it
    defaults to the empty string ''. When you subscribe to this socket, you must
    set your subscription to an empty string, or to at least the first letter of
    the binary representation of this string to ensure you receive any messages
    from this handler.
    If you use the default empty string root topic, messages will begin with
    the binary representation of the log level string (INFO, WARN, etc.).
    Note that ZMQ SUB sockets can have multiple subscriptions.
    """
    self._root_topic = root_topic