Who said "The future is unwritten; we get to create it."?

This quote is attributed to Supergirl.

The future is unwritten; we get to create it. - Supergirl

"The future is unwritten; we get to create it."

Supergirl

"I'm not just Kara Danvers. I'm also Supergirl."

"Being a hero isn't just about having powers. It's about what you choose to do with them."

"I have to believe that there's good in people, even when they give me reason not to."

"My family is what makes me strong."