diff --git a/pyproject.toml b/pyproject.toml
index a922c1fb5..404e48616 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -74,6 +74,7 @@ all = [
     "pyvespa",
     "lancedb",
     "mysql-connector-python",
+    "ujson",
 ]
 
 qdrant          = [ "qdrant-client" ]
diff --git a/vectordb_bench/backend/clients/tencent_elasticsearch/tencent_elasticsearch.py b/vectordb_bench/backend/clients/tencent_elasticsearch/tencent_elasticsearch.py
index 887797212..eb69a730d 100644
--- a/vectordb_bench/backend/clients/tencent_elasticsearch/tencent_elasticsearch.py
+++ b/vectordb_bench/backend/clients/tencent_elasticsearch/tencent_elasticsearch.py
@@ -2,10 +2,9 @@
 import time
 from contextlib import contextmanager
 
-from vectordb_bench.backend.filter import Filter, FilterOp
+from vectordb_bench.backend.filter import FilterOp
 
 from ..elastic_cloud.elastic_cloud import ElasticCloud
-from .config import TencentElasticsearchIndexConfig
 
 for logger in ("elasticsearch", "elastic_transport"):
     logging.getLogger(logger).setLevel(logging.WARNING)