diff --git a/lib/lyx2lyx/lyx_1_6.py b/lib/lyx2lyx/lyx_1_6.py
index e1ed5e670f..38728c6e07 100644
--- a/lib/lyx2lyx/lyx_1_6.py
+++ b/lib/lyx2lyx/lyx_1_6.py
@@ -1777,7 +1777,7 @@ def revert_module_names(document):
     return
   newmodlist = []
   for mod in modlist:
-    if modulemap.has_key(mod):
+    if mod in modulemap:
       newmodlist.append(modulemap[mod])
     else:
       document.warning("Can't find module %s in the module map!" % mod)