How to use the elasticsearch5.ConnectionError function in elasticsearch5

def does_index_exist(
    app_namespace, index_name, es_host=None, es_client=None, connect_timeout=2
):
    """Return boolean flag to indicate whether the specified index exists."""

    es_client = es_client or create_es_client(es_host)
    scoped_index_name = get_scoped_index_name(app_namespace, index_name)

    try:
        # Confirm ES connection with a shorter timeout
        es_client.cluster.health(request_timeout=connect_timeout)
        return es_client.indices.exists(index=scoped_index_name)
    except EsConnectionError as e:
        logger.debug(
            "Unable to connect to Elasticsearch: %s details: %s", e.error, e.info
        )
        raise KnowledgeBaseConnectionError(es_host=es_client.transport.hosts)
    except TransportError as e:
        logger.error(
            "Unexpected error occurred when sending requests to Elasticsearch: %s "
            "Status code: %s details: %s",
            e.error,
            e.status_code,
            e.info,
        )
        raise KnowledgeBaseError
    except ElasticsearchException:
        raise KnowledgeBaseError

# load field info from local cache
        index_info = self._es_field_info.get(index, {})

        if not index_info:
            try:
                # TODO: move the ES API call logic to ES helper
                self._es_field_info[index] = {}
                res = self._es_client.indices.get(index=index)
                all_field_info = res[index]["mappings"]["document"]["properties"]
                for field_name in all_field_info:
                    field_type = all_field_info[field_name].get("type")
                    self._es_field_info[index][field_name] = FieldInfo(
                        field_name, field_type
                    )
            except EsConnectionError as e:
                logger.error(
                    "Unable to connect to Elasticsearch: %s details: %s",
                    e.error,
                    e.info,
                )
                raise KnowledgeBaseConnectionError(
                    es_host=self._es_client.transport.hosts
                )
            except TransportError as e:
                logger.error(
                    "Unexpected error occurred when sending requests to Elasticsearch: %s "
                    "Status code: %s details: %s",
                    e.error,
                    e.status_code,
                    e.info,
                )