def emit(self, signalName, *args, **kwargs):
        """
        Emits a signal by name if it exists. Any additional args or kwargs are passed to the signal
        :param signalName: the signal name to emit
        """
        assert signalName in self, "%s is not a registered signal" % signalName
        self[signalName].emit(*args, **kwargs)
Emits a signal by name if it exists. Any additional args or kwargs are passed to the signal
        :param signalName: the signal name to emit