replace has_key with 'in' operator
diff --git a/Lib/idlelib/TreeWidget.py b/Lib/idlelib/TreeWidget.py
index 5299e0e..842f788 100644
--- a/Lib/idlelib/TreeWidget.py
+++ b/Lib/idlelib/TreeWidget.py
@@ -409,7 +409,7 @@
 
 class ScrolledCanvas:
     def __init__(self, master, **opts):
-        if not opts.has_key('yscrollincrement'):
+        if 'yscrollincrement' not in opts:
             opts['yscrollincrement'] = 17
         self.master = master
         self.frame = Frame(master)