def addHandler(self, hdlr):
        if not (hdlr in self.handlers):
            self.handlers.append(hdlr)
Use the deployer's ``IBlockDeviceAPI`` to detach the volume.
dataset/ETHPy150Open deanhiller/databus/webapp/play1.3.x/python/Lib/logging/__init__.py/Logger.addHandler--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/blockdevice.py/DetachVolume.run