diff --git a/PIL/PyAccess.py b/PIL/PyAccess.py
index 28829051d..a3f1c3909 100644
--- a/PIL/PyAccess.py
+++ b/PIL/PyAccess.py
@@ -54,7 +54,7 @@ class PyAccess(object):
             print (vals)
         self._post_init()
 
-    def _post_init():
+    def _post_init(self):
         pass
 
     def __setitem__(self, xy, color):