Possibly practicing for having to "Shoot to Wound," a police officer shot a Harlem teen in the arm yesterday after the teen reportedly opened fire on the cop. Shawn Lambert, 17, was apparently visibly armed at 1:30 a.m. yesterday, and began shooting at the cop, who in return fired off five rounds. Lambert ran away after being shot in the arm, but cops followed the blood trail back to his apartment. The teen is currently recovering in Harlem Hospital.