diff --git a/git_cl.py b/git_cl.py
index 4c882e6..2f26068 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -3605,7 +3605,7 @@
       if issue:
         issue_branch_map.setdefault(int(issue), []).append(branch)
     if not args:
-      args = sorted(issue_branch_map.iterkeys())
+      args = sorted(issue_branch_map.keys())
     result = {}
     for issue in args:
       try: