diff --git a/andes/system.py b/andes/system.py
index c0c216e07..5e8809d29 100644
--- a/andes/system.py
+++ b/andes/system.py
@@ -40,7 +40,6 @@
 
 logger = logging.getLogger(__name__)
 dill.settings['recurse'] = True
-pycode = None
 
 
 class ExistingModels: