GuidesEvaluationString EvaluatorsExact MatchOn this pageExact MatchProbably the simplest ways to evaluate an LLM or runnable's string output against a reference label is by a simple string equivalence.This can be accessed using the exact_match evaluator.from langchain.evaluation import ExactMatchStringEvaluatorevaluator = ExactMatchStringEvaluator()Alternatively via the loader:from langchain.evaluation import load_evaluatorevaluator = load_evaluator("exact_match")evaluator.evaluate_strings(    prediction="1 LLM.",    reference="2 llm",)    {'score': 0}evaluator.evaluate_strings(    prediction="LangChain",    reference="langchain",)    {'score': 0}Configure the ExactMatchStringEvaluator​You can relax the "exactness" when comparing strings.evaluator = ExactMatchStringEvaluator(    ignore_case=True,    ignore_numbers=True,    ignore_punctuation=True,)# Alternatively# evaluator = load_evaluator("exact_match", ignore_case=True, ignore_numbers=True, ignore_punctuation=True)evaluator.evaluate_strings(    prediction="1 LLM.",    reference="2 llm",)    {'score': 1}PreviousEmbedding DistanceNextRegex MatchConfigure the ExactMatchStringEvaluator