diff --git a/python/paddle/fluid/dygraph/dygraph_to_static/utils.py b/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
index 58cad1cfa4272e93d9463817aa3de7667c6e07bf..6636bf7c4b40514c972541b35f5f7f5ff79058ee 100644
--- a/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
+++ b/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
@@ -369,13 +369,14 @@ def ast_to_func(ast_root, dyfunc, delete_on_exit=True):
     function, the other inner functions are invisible for the decorated function.
     """
 
-    def remove_file(filepath):
+    def remove_if_exit(filepath):
         if os.path.exists(filepath):
             os.remove(filepath)
 
     source = ast_to_source_code(ast_root)
     import_fluid = "import paddle.fluid as fluid\n"
     source = import_fluid + source
+
     if six.PY2:
         source = source.encode('utf-8')
         f = tempfile.NamedTemporaryFile(mode='w', suffix='.py', delete=False)
@@ -387,8 +388,8 @@ def ast_to_func(ast_root, dyfunc, delete_on_exit=True):
         f.write(source)
 
     if delete_on_exit:
-        atexit.register(lambda: remove_file(f.name))
-        atexit.register(lambda: remove_file(f.name[:-3] + ".pyc"))
+        atexit.register(lambda: remove_if_exit(f.name))
+        atexit.register(lambda: remove_if_exit(f.name[:-3] + ".pyc"))
 
     module = imp.load_source(module_name, f.name)
     func_name = dyfunc.__name__