Question: Who sings the lead song in a 2010 romantic comedy starring Jessica Alba, Kathy Bates, and Bradley Cooper?
Sentence (from "Valentine's Day (2010 film)"): The film consists of an ensemble cast led by Jessica Alba, Kathy Bates, Jessica Biel, Bradley Cooper, Eric Dane, Patrick Dempsey, Héctor Elizondo, Jamie Foxx, Jennifer Garner, Topher Grace, Anne Hathaway, Ashton Kutcher, Queen Latifah, Taylor Lautner, George Lopez, Shirley MacLaine, Emma Roberts, Julia Roberts, Carter Jenkins, and Taylor Swift in her film debut.
Relevant evidence: Yes