I'm a big fan of using different samples and inspirations for hip-hop tracks, and this one doesn't disappoint. The track is B.H.O'z (ie. Boss Hogg Outlawz), by Slim Thug feat. Kyleon, Daily and Chris Ward. If you're over 30 and think the melody sounds familiar, it's because they've flipped the Creedence Clearwater Revival's Proud Mary.