Russell Westbrook couldn't have looked happier right after his big trade to the Lakers ... hitting an L.A. hot spot with Kevin Hart on Thursday -- smiling from ear-to-ear!!!
Of course, Brodie was the centerpiece of a MASSIVE deal between the Lake Show and Washington Wizards ... with Kyle Kuzma, Kentavious Caldwell-Pope, Montrezl Harrell and draft picks getting shipped out of town for the 2017 MVP.
Westbrook -- a SoCal native -- wasted no time celebrating his big homecoming .