diff --git a/common/lib/xmodule/setup.py b/common/lib/xmodule/setup.py
index bf49987511..792eea27b5 100644
--- a/common/lib/xmodule/setup.py
+++ b/common/lib/xmodule/setup.py
@@ -45,7 +45,7 @@ setup(
             "static_tab = xmodule.html_module:StaticTabDescriptor",
             "custom_tag_template = xmodule.raw_module:RawDescriptor",
             "about = xmodule.html_module:AboutDescriptor",
-			"graphical_slider_tool = xmodule.gst_module:GraphicalSliderToolDescriptor,
+			"graphical_slider_tool = xmodule.gst_module:GraphicalSliderToolDescriptor",
             "wrapper = xmodule.wrapper_module:WrapperDescriptor",
         ],
     }