diff --git a/websocket/__init__.py b/websocket/__init__.py
index fa4b98b..f294533 100644
--- a/websocket/__init__.py
+++ b/websocket/__init__.py
@@ -20,3 +20,5 @@ Copyright (C) 2010 Hiroki Ohtani(liris)
 """
 from ._core import *
 from ._app import WebSocketApp
+
+__version__ = "0.20.0"