Where did this song used in Emu's World originally come from?

Youtuber VideotapeFTW has been unable to identify this song used in an episode of Emu's World in 1984.
All the musical numbers in Rod Hull's various Emu programmes featured covers from either musicals or pop songs, and this song certainly sounds like it was written for a classic (children's?) musical. Does anybody know which one?

https://www.youtube.com/watch?v=pXNDHCSxeWc

Here are the lyrics:
Can I just convey
The thing I'm trying to say?
You've got to go your own way
But there is something can maybe make the day...

Putting your best foot forward
Everywhere you go,
You know your confidence will carry you through.
Putting your best foot forward,
Everyone'll say
You do your best in everything that you do.

Putting your best foot forward
Could create a style,
So where's the smile?
Create the style!
Putting your best foot forward,
You can lead the field
And be a real delightful character too.

Your nose to the grindstone,
Your shoulder to the wheel.
Your back against the wall,
'Cos it might fall
Around your heels, around your knees, around your feet.

Putting your best foot forward,
Maybe you can say
You'll win the day.
But who can say?
Putting your best foot forward,
There could be the prize
Before your eyes to your surprise,
And it's true.

How would you advise
Other kids our size?
How would I advise
Other kids your size?
It is wise, I'd say,
It is wise, (Too true!)
To put your best foot forward in every single thing that you do.

Putting your best foot forward,
And we must confess
You could be (best?).
But who can guess?
Putting your best foot forward
Doesn't win the race,
It's no disgrace to do the best you can do.

After all advice (...we'll?) turn to you.
Well, I've told you twice, and it still holds true:
It is wise, (That's one!)
It is wise, (That's two!)
To put your best foot forward,
Your best foot forward,
Your best foot forward,
Your best foot forward,
To put your best foot forward in every single thing that you do.