diff --git a/src/searchengine/nova3/nova2.py b/src/searchengine/nova3/nova2.py
old mode 100755
new mode 100644
index f02b324f4..2c5963beb
--- a/src/searchengine/nova3/nova2.py
+++ b/src/searchengine/nova3/nova2.py
@@ -107,7 +107,7 @@ def initialize_engines(found_engines):
     for engine_name in found_engines:
         # import engine
         engine = get_engine(engine_name)
-        if engine == None:
+        if engine is None:
             continue
         supported_engines.append(engine_name)