(self, event)
Abstract method to handle a `TopologyOpenedEvent`.

        :Parameters:
          - `event`: An instance of :class:`TopologyOpenedEvent`.
Abstract method to handle a `TopologyOpenedEvent`.
Abstract method to handle a TopologyOpenedEvent .
def opened(self, event):
        """Abstract method to handle a `TopologyOpenedEvent`.

        :Parameters:
          - `event`: An instance of :class:`TopologyOpenedEvent`.
        """
        raise NotImplementedError
def opened ( self , event ) : raise NotImplementedError