diff --git a/backtrader/signal.py b/backtrader/signal.py
index <HASH>..<HASH> 100644
--- a/backtrader/signal.py
+++ b/backtrader/signal.py
@@ -21,6 +21,7 @@
 from __future__ import (absolute_import, division, print_function,
                         unicode_literals)
 
+import backtrader as bt
 
 (
 
@@ -32,3 +33,7 @@ from __future__ import (absolute_import, division, print_function,
     SIGNAL_SHORTEXIT
 
 ) = range(6)
+
+
+class Signal(bt.Indicator):
+    lines = ('signal',)
Add a Signal class to make it easier to subclass and create a signal