Helper method to send a message to current running app.

def send_app_message(self, namespace, message, inc_session_id=False,
                         callback_function_param=False):
        """ Helper method to send a message to current running app. """
        if namespace not in self.app_namespaces:
            raise UnsupportedNamespace(
                ("Namespace {} is not supported by current app. "
                 "Supported are {}").format(namespace,
                                            ", ".join(self.app_namespaces)))

        return self.send_message(self.destination_id, namespace, message,
                                 inc_session_id, callback_function_param)