More 2to3 fixes in the Tools directory. Fixes #2893.
diff --git a/Tools/i18n/msgfmt.py b/Tools/i18n/msgfmt.py
index f4466b4..860e4ea 100755
--- a/Tools/i18n/msgfmt.py
+++ b/Tools/i18n/msgfmt.py
@@ -56,9 +56,8 @@
 def generate():
     "Return the generated output."
     global MESSAGES
-    keys = MESSAGES.keys()
     # the keys are sorted in the .mo file
-    keys.sort()
+    keys = sorted(MESSAGES.keys())
     offsets = []
     ids = strs = ''
     for id in keys: