Who said "Perseverance is choosing to keep going."?

This quote is attributed to Courage the Cowardly Dog.

Perseverance is choosing to keep going. - Courage the Cowardly Dog

"Perseverance is choosing to keep going."

Courage the Cowardly Dog Perseverance

"Courage, the cowardly dog."

"What's wrong, Muriel?"

"Oh, the things I do for love."

"Stupid Eustace!"

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."