code: def test_save_load(self):
      dataframes_to_test = spark.createDataFrame(
          [(0, "docker"), (0, "spark"), (1, "python")],
          ["label", "technology"],
      )
      temp_dir = "tmp"
      os.mkdir(temp_dir)
      path = os.path.join(temp_dir, "langchainTransformer")
      self.langchainTransformer.save(path)
      loaded_transformer = LangchainTransformer.load(path)
      self._assert_chain_output(loaded_transformer, dataframes_to_test)
  
file_path: SynapseML/cognitive/src/test/python/synapsemltest/services/langchain/test_LangchainTransform.py
imports: import os, json, subprocess, unittest
  from langchain.chains import LLMChain
  from langchain.prompts import PromptTemplate
  from langchain.llms import AzureOpenAI
  from synapse.ml.services.langchain import LangchainTransformer
  from synapsemltest.spark import *
label_desc: Use image node_id 8 for calling the LangchainTransformTest obj's underlying member method code with example usage: obj.test_save_load() without return types