code: def saveLightGBMModel(
      self,
      lightgbm_model,
      path,
      crypto_mode="plain_text",
      primary_key_name="",
  ):
      if isinstance(crypto_mode, CryptoMode):
          crypto_mode = crypto_mode.value
      return callBigDlFunc(
          self.bigdl_type,
          "saveLightGBMModel",
          self.value,
          lightgbm_model._java_obj,
          path,
          crypto_mode,
          primary_key_name,
      )
  
imports: from bigdl.ppml.api import *
  from bigdl.ppml.utils.log4Error import *
  from enum import Enum
  from pyspark.sql import SparkSession
  from pyspark.ml.wrapper import JavaParams
label_desc: Use image node_id 6 for calling the PPMLContext obj's underlying member method code with example usage: obj.saveLightGBMModel(lightgbm_model, path, crypto_mode, primary_key_name) and returns: callBigDlFunc