Hiphop track ID from The Wire's title episode

Can't figure it out by googling. It's the first cut from a scene beginning 7:54 of S01E06, with D'Angelo getting dressed. See subbed video.

Some guessed-at lyrics:
the beat goes on like one of those nights that goes on too long, maybe one of those songs that could have got cut the fuck off a long time ago my friends...
like a nigga got to see from babylon...
about the laws of hip hop, laws you know those laws
there's laws of hip hop ya dig and you should have read that book i recommended cuz if you did you would see....
now if you don't have a hip hop license...