code: def __str__(self):
      return self.value
  
file_path: FATE/python/fate/arch/federation/_builder.py
imports: import typing
  from enum import Enum
  from fate.arch.federation.api import PartyMeta
  from fate.arch.config import cfg
label_desc: Use image node_id 2 for calling the FederationEngine obj's underlying member method code with example usage: obj.__str__() and returns: self