(self, message_listener)
Internal method used by the protocol message implementation.
    Clients should not call this directly.

    Sets a listener that this message will call on certain state transitions.

    The purpose of this method is to register back-edges from children to
    parents at runtime, for the purpose of setting "has" bits and
    byte-size-dirty bits in the parent and ancestor objects whenever a child or
    descendant object is modified.

    If the client wants to disconnect this Message from the object tree, she
    explicitly sets callback to None.

    If message_listener is None, unregisters any existing listener.  Otherwise,
    message_listener must implement the MessageListener interface in
    internal/message_listener.py, and we discard any listener registered
    via a previous _SetListener() call.
Internal method used by the protocol message implementation.
    Clients should not call this directly.
Internal method used by the protocol message implementation . Clients should not call this directly .
def _SetListener(self, message_listener):
    """Internal method used by the protocol message implementation.
    Clients should not call this directly.

    Sets a listener that this message will call on certain state transitions.

    The purpose of this method is to register back-edges from children to
    parents at runtime, for the purpose of setting "has" bits and
    byte-size-dirty bits in the parent and ancestor objects whenever a child or
    descendant object is modified.

    If the client wants to disconnect this Message from the object tree, she
    explicitly sets callback to None.

    If message_listener is None, unregisters any existing listener.  Otherwise,
    message_listener must implement the MessageListener interface in
    internal/message_listener.py, and we discard any listener registered
    via a previous _SetListener() call.
    """
    raise NotImplementedError
def _SetListener ( self , message_listener ) : raise NotImplementedError