def test_run(self):
        mountroot = mountroot_for_test(self)
        mountpoint = mountroot.child(b"mount-test")
        self._run_success_test(mountpoint)
``CreateFilesystem.run`` initializes a block device with a filesystem
dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/test/test_blockdevice.py/MountBlockDeviceTests.test_run