@staticmethod
def get_elastic_mappings(es_major):
    """Get Elasticsearch mapping.

        Different versions of Elasticsearch may need specific versions
        of the mapping, thus using es_major to potentially provide
        different mappings.

        When the mapping depends on the version of Kibiter/Kibana,
        we will use the Elasticsearch version anyway, since they should
        be paired (same major version for 5 and larger, ES major version 2
        for Kibiter/Kibana major version 4).

        :param es_major: major version of Elasticsearch, as string
        :returns:        dictionary with a key, 'items', with the mapping
        """
    mapping = '{}'
    return {'items': mapping}
