[Liberty Valance]

We're off to see the Wizard, The Wonderful Wizard of Oz.
You'll find he is a whiz of a Wiz! If ever a Wiz! there was.
If ever oh ever a Wiz! there was The Wizard of Oz is one because,
Because, because, because, because, because.
Because of the wonderful things he does.
We're off to see the Wizard. The Wonderful Wizard of Oz.

[dr_lew]

Reviewing the "curtain scene", the opening lines of that clip seemed especially pertinent:

"Do not arouse the wrath of the great and powerful Oz! "I said come back tomorrow!"

"If you were really great and powerful you'd keep your promises!"