diff --git a/IPython/core/completer.py b/IPython/core/completer.py
index 9237929..167acbd 100644
--- a/IPython/core/completer.py
+++ b/IPython/core/completer.py
@@ -1542,7 +1542,7 @@ class IPCompleter(Completer):
                   inspect.Parameter.POSITIONAL_OR_KEYWORD)
 
         try:
-            sig = inspect.signature(call_obj)
+            sig = inspect.signature(obj)
             ret.extend(k for k, v in sig.parameters.items() if
                        v.kind in _keeps)
         except ValueError: