Question: "I Was a Fool" is a song written and performed by Canadian duo Tegan and Sara, inspired by one of Rihanna's singles ,Unfaithful from her second studio album "A Girl like Me" (2006), written by who?
Sentence (from "Unfaithful (song)"): It was written by Shaffer "Ne-Yo" Smith with the song's producers StarGate.
Relevant evidence: Yes