Ernie what s the name of that song

There's nothing like a smile on your face,
La-de-da-de-dum,
What's the name of that song?
There's nothing like a smile on your face,
There's a smile on your face,
What's the name of that song?
It goes la-de-da-de-dum,
La-de-da-de-dum,
Something something birds.
La-de-da-de-dum,
La-de-da-dee,
I wish I remembered the words.
There's nothing like a smile on your face,
There's a smile on your face,
What's the name of that song?
La-de-da-dum,
La-de-da-dum,
I'd like to sing right along!
I've heard it said,
With words and music
A fellow can't go wrong.
So la-de-da-de-dum,
La-de-da-de-dum,
What's the name of that song?
There's nothing like a smile on your face,
There's a smile on your face,
What's the name of that song?
The-Dum,
The-Dum,
We need the name of that song!
It goes the-dumb,
The-dumb,
Something, something nice.
La-de-da-de-dum,
La-de-da-dee,
I think it repeats itself twice!
There's nothing like a smile on your face,
There's a smile on your face,
What's the name of that song?
There's nothing like it,
There's nothing like it,
I know the name of that song!
It's called--now wait,
I think I got it!
Oh, no--I must be wrong--
So la-de-da-de-dum,
La-da-de-dum,
What's the name of that song?
(Honkers) Honk-ee-honk-ee-honk, honk-ee-honk-ee-honk
(Oscar-annoyed) What's the name of that song?
(All) La-de-da-de, La-de-da-de
(Oscar) They keep on singing that song
They go La-de-da-de -dum, La-de-da-de-dum
The-dum-the-dum,
The-dum-the-dum, The-dum-the-dum,
They start it all over again.
La-de-da-de-dum, La-de-da-dum
(Gordon) Something shining above.
(two-headed monsters sing some unintelligible words that end with something that rhymes with above)
We can't help singing La-de-da-de-dum
Loud and clear and strong . . . .
But La-de-da-de-dum, La-de-da-de-dum
La-de-da-de-dum, La-de-da-de-dum
La-de-da-de-dum, Laaaaaaaaaaa!
What IS the name of that song?