Question: Untitled 2 is a jazz rap song by American rapper Kendrick Lamar featured on a compilation album that was released on?
Sentence (from "Untitled Unmastered"): It consists of previously unreleased demos that originated during the recording of Lamar's album "To Pimp a Butterfly" (2015), continuing that work's exploration of politically-charged and psychological themes, as well as its experimentation with free jazz, soul, avant-garde, and funk styles.
Relevant evidence: No