Args:
            index_name (`str`):
                The `index_name`/identifier of the index. This is the index name that is used to call `get_nearest` or `search`.
            es_index_name (`str`):
                The name of elasticsearch index to load.
            host (`str`, *optional*, defaults to `localhost`):
                Host of where ElasticSearch is running.
            port (`str`, *optional*, defaults to `9200`):
                Port of where ElasticSearch is running.
            es_client (`elasticsearch.Elasticsearch`, *optional*):
                The elasticsearch client used to create the index if host and port are `None`.
            es_index_config (`dict`, *optional*):
                The configuration of the elasticsearch index.
                Default config is:
                    ```
                    {
                        "settings": {
                            "number_of_shards": 1,