Open Source, Llamaindex, Gpt 4, Llm, OpenAI.
service_context gpt4_service_context = ServiceContext.from_defaults( llm=gpt4_llm, callback_manager=callback_manager ) # CorrectnessEvaluator with GPT-4 model gpt4_correctness_evaluator = CorrectnessEvaluator( service_context=gpt4_service_context, # parser_function=parser_function, ) #