Issue 22823: Use set literal in idlelib.
diff --git a/Lib/idlelib/CodeContext.py b/Lib/idlelib/CodeContext.py
index 2f6f737..bb0cc9c 100644
--- a/Lib/idlelib/CodeContext.py
+++ b/Lib/idlelib/CodeContext.py
@@ -15,8 +15,8 @@
from sys import maxint as INFINITY
from idlelib.configHandler import idleConf
-BLOCKOPENERS = set(["class", "def", "elif", "else", "except", "finally", "for",
- "if", "try", "while", "with"])
+BLOCKOPENERS = {"class", "def", "elif", "else", "except", "finally", "for",
+ "if", "try", "while", "with"}
UPDATEINTERVAL = 100 # millisec
FONTUPDATEINTERVAL = 1000 # millisec