code: def _assert_chain_output(self, transformer, dataframe):
      transformed_df = transformer.transform(dataframe)
      collected_transformed_df = transformed_df.collect()
      input_col_values = [
          row.technology for row in collected_transformed_df
      ]
      output_col_values = [
          row.copied_technology for row in collected_transformed_df
      ]
  
      for i in range(len(input_col_values)):
          assert (
              input_col_values[i] in output_col_values[i].lower()
          ), f"output column value {output_col_values[i]} doesn't contain input column value {input_col_values[i]}"
  
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 4 for calling the LangchainTransformTest obj's underlying member method code with example usage: obj._assert_chain_output(transformer, dataframe) without return types