code: def saveImpl(self, path: str) -> None:
      params = self.instance._paramMap
      modifiedParamMap = {}
      for p in params:
          if "chain" in p.name:
              # For parameter chain, we need to first
              # serialize it, and then pass it to
              # parameter map.
              param_value = self._chain_serializer(params[p])
          else:
              param_value = params[p]
          modifiedParamMap[p.name] = param_value
      DefaultParamsWriter.saveMetadata(
          self.instance, path, self.sc, paramMap=modifiedParamMap
      )
  
imports: import json
  from os import error
  from langchain.chains.loading import load_chain_from_config
  from pyspark import keyword_only
  from pyspark.ml import Transformer
  from pyspark.ml.param.shared import HasInputCol, HasOutputCol, Param
  from pyspark.ml.util import DefaultParamsReadable, DefaultParamsWritable, DefaultParamsReader, DefaultParamsWriter
  from pyspark.sql.functions import udf, col
  from pyspark.sql.types import StructType, StructField, StringType
  from typing import cast, Optional, TypeVar, Type
  from synapse.ml.core.platform import running_on_synapse_internal
label_desc: Use image node_id 2 for calling the LangchainTransformerParamsWriter obj's underlying member method code with example usage: obj.saveImpl(path) without return types