code: def decode_mode(cls, v: bytes) -> int:
      return struct.unpack("!B", v[:1])[0]
  
imports: import io
  import logging
  import pickle
  import struct
  import typing
  from typing import Any, List, Tuple, TypeVar
  from fate.arch.config import cfg
  from ._table_meta import TableMeta
  from ._type import PartyMeta
label_desc: Use image node_id 3 for calling the _FederationBytesCoder obj's underlying member method code with example usage: obj.decode_mode(cls, v) and returns: struct