code: def keygen(key_size):
      sk, pk, coder = _keygen(key_size)
      return SK(sk), PK(pk), Coder(coder)
  
imports: from typing import List, Optional, Tuple
  import torch
  from fate_utils.ou import CiphertextVector, PlaintextVector
  from fate_utils.ou import Coder
  from fate_utils.ou import Evaluator
  from fate_utils.ou import PK
  from fate_utils.ou import SK
  from fate_utils.ou import keygen
  from .type import TensorEvaluator
label_desc: Use image node_id 1 for calling a global function with example usage: keygen(key_size) and returns: SK,  PK,  Coder