^There's an intersection in a town near where I live. The main street is part of the Trans-Canada highway. Heading south from the cross street at that intersection, there is a stop sign and this sign:
Now, if you think about it, following the directions on the sign will bring you right back to the same spot. When I encountered that situation, needing to turn left, quickly figured out that I would have to drive through the intersection and then start turning right 3 times, which would bring me back to that intersection heading in the correct direction to go straight through, effectively completing my left-hand turn.