diff --git a/src/utils.py b/src/utils.py
index 10c3c36d0..ad63ddcfc 100755
--- a/src/utils.py
+++ b/src/utils.py
@@ -460,6 +460,7 @@ class IterableMap(object):
     def iterkeys(self):
         for (key, _) in self.iteritems():
             yield key
+    __iter__ = iterkeys
 
     def itervalues(self):
         for (_, value) in self.iteritems():