Who said "Perseverance is just refusing to give up."?

This quote is attributed to Droopy.

Perseverance is just refusing to give up. - Droopy

"Perseverance is just refusing to give up."

Droopy Perseverance

"I'm so happy."

"Hello, I'm so glad to see you."

"That makes me so sad."

"I'm afraid I have some bad news."

"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."