Create a new group trigger.

        :param trigger: Group member trigger to be created
        :return: The created group Trigger

def create_group(self, trigger):
        """
        Create a new group trigger.

        :param trigger: Group member trigger to be created
        :return: The created group Trigger
        """
        data = self._serialize_object(trigger)
        return Trigger(self._post(self._service_url(['triggers', 'groups']), data))