def release(self):
        assert self.locked, "Tried to release an unlocked lock"
        self.locked = False
        if self.waiting:
            # someone is waiting to acquire lock
            self.locked = True
            d = self.waiting.pop(0)
            d.callback(self)
Return the edge boundary. 
dataset/ETHPy150Open twisted/twisted/twisted/internet/defer.py/DeferredLock.release--crossover with--dataset/ETHPy150Open gkno/gkno_launcher/src/networkx/algorithms/boundary.py/edge_boundary