def query(cls, visibility=None, api=None):
        """Query ( List ) datasets
        :param visibility: If provided as 'public', retrieves public datasets
        :param api: Api instance
        :return: Collection object
        """
        api = api if api else cls._API

        return super(Dataset, cls)._query(
            url=cls._URL['query'],
            visibility=visibility,
            fields='_all', api=api
        )