diff --git a/abl/abducer/kb.py b/abl/abducer/kb.py
index 5b82f03..9009940 100644
--- a/abl/abducer/kb.py
+++ b/abl/abducer/kb.py
@@ -291,7 +291,7 @@ class prolog_KB(KBBase):
 
 
 class RegKB(KBBase):
-    def __init__(self, pseudo_label_list=None, len_list=None, GKB_flag=False, max_err=1e-3):
+    def __init__(self, pseudo_label_list, len_list, GKB_flag, max_err):
         super().__init__(pseudo_label_list, len_list, GKB_flag, max_err)
 
     def _find_candidate_GKB(self, pred_res, key):
@@ -361,4 +361,4 @@ class HWF_KB(RegKB):
 import time
 
 if __name__ == "__main__":
-    pass
\ No newline at end of file
+    pass