diff --git a/setup.py b/setup.py
index aa087a9..3bd9d35 100644
--- a/setup.py
+++ b/setup.py
@@ -688,8 +688,7 @@
                         # ignore this header, it didn't contain a version number
                         if db_setup_debug: print("db.h: unsupported version", db_ver, "in", d)
 
-            db_found_vers = db_ver_inc_map.keys()
-            db_found_vers.sort()
+            db_found_vers = sorted(db_ver_inc_map.keys())
 
             while db_found_vers:
                 db_ver = db_found_vers.pop()