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

    """
    super(RADOSBlockDevice, 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.driver, self.rbd_name = unique_id
    self.rbd_pool = params[constants.LDP_POOL]

    self.major = self.minor = None
    self.Attach()
dataset/ETHPy150Open ganeti/ganeti/lib/storage/bdev.py/RADOSBlockDevice.__init__/swapped operands of `%`