def __init__(self, unique_id, children, size, params, dyn_params, *args):
    """Attaches to a LV device.

    The unique_id is a tuple (vg_name, lv_name)

    """
    super(LogicalVolume, self).__init__(unique_id, children, size, params,
                                        dyn_params, *args)
    if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
      raise ValueError(str(unique_id) % "Invalid configuration data %s")
    self._vg_name, self._lv_name = unique_id
    self._ValidateName(self._vg_name)
    self._ValidateName(self._lv_name)
    self.dev_path = utils.PathJoin("/dev", self._vg_name, self._lv_name)
    self._degraded = True
    self.major = self.minor = self.pe_size = self.stripe_count = None
    self.pv_names = None
    self.Attach()
dataset/ETHPy150Open ganeti/ganeti/lib/storage/bdev.py/LogicalVolume.__init__/swapped operands of `%`