diff --git a/verl/single_controller/base/worker.py b/verl/single_controller/base/worker.py
index ad6bab93..46d88e31 100644
--- a/verl/single_controller/base/worker.py
+++ b/verl/single_controller/base/worker.py
@@ -45,6 +45,7 @@ def get_node_ip_by_sdk():
             elif os.getenv("WG_BACKEND", None) == "torch_rpc":
                 from verl.single_controller.torchrpc.k8s_client import get_ip_addr
                 return get_ip_addr()
+            ## test it.
             return None
 
         host_ipv4 = os.getenv("MY_HOST_IP", None)