Watch Conor Oberst and The Felice Brothers Cover Tom Petty's "Walls (Circus)"

Conor Oberst and the Felice Brothers, who are currently touring as his backing band, paid tribute to the late Tom Petty by covering the singer-songwriter's 1996 hit with the Heartbreakers, "Walls (Circus)," during a set at San Francisco's Hardly Strictly Bluegrass Festival this weekend. "I think as human beings, as homosapiens, we need these kind of…