Who said "I don't believe in giving up. That's not in my nature."?

This quote is attributed to Hawkeye / Clint Barton.

I don't believe in giving up. That's not in my nature. - Hawkeye / Clint Barton

"I don't believe in giving up. That's not in my nature."

Hawkeye / Clint Barton Perseverance

"I'm just a guy with a bow and arrow."

"Sometimes the smallest things take up the most room in your heart."

"You know what the problem is? You're always looking for the next big thing, when sometimes it's right in front of you."

"I can't miss. Well, I can miss, but I don't very often."

"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."