diff --git a/python/examples/lac/lac_web_service.py b/python/examples/lac/lac_web_service.py
index 4a58c6a43caea4045220546488226da121bfdc17..fe06224125ccc305df19dad0805d1e28563ed229 100644
--- a/python/examples/lac/lac_web_service.py
+++ b/python/examples/lac/lac_web_service.py
@@ -25,8 +25,14 @@ class LACService(WebService):
         if "words" not in feed:
             raise ("feed data error!")
         feed_data = self.reader.process(feed["words"])
+        fetch = ["crf_decode"]
         return {"words": feed_data}, fetch
 
+    def postprocess(self, feed={}, fetch=[], fetch_map={}):
+        segs = self.reader.parse_result(
+            feed["words"], fetch_map["crf_decode"])
+        return {"word_seg": "|".join(segs)}
+
 
 lac_service = LACService(name="lac")
 lac_service.load_model_config(sys.argv[1])