[Solved] You wrote this code to create evaluation examples but get an error: examples = [{"query": "Who wrote Hamlet?", "answer": "Shakespeare"}] chain = QAEvalChain.from_llm(llm=some_llm) results = chain.... | LangChain

LangChain - Evaluation and Testing

You wrote this code to create evaluation examples but get an error:

examples = [{"query": "Who wrote Hamlet?", "answer": "Shakespeare"}]
chain = QAEvalChain.from_llm(llm=some_llm)
results = chain.evaluate(examples)
print(results)

What is the likely cause of the error?

AThe variable some_llm is not defined

BThe key 'answer' should be 'expected_answer' in the example dictionary

CQAEvalChain does not have an evaluate method

DThe examples list should be empty

Step-by-Step Solution

Solution:

Step 1: Check example dictionary keys
LangChain expects 'expected_answer' key, not 'answer', for evaluation examples.
Step 2: Identify mismatch causing error
Using 'answer' instead of 'expected_answer' causes the chain to fail reading expected answers.
Final Answer:
The key 'answer' should be 'expected_answer' in the example dictionary -> Option B
Quick Check:
Correct key name = 'expected_answer' [OK]

Quick Trick: Use 'expected_answer' key, not 'answer' in examples [OK]

Common Mistakes:

MISTAKES

Using wrong key names in example dictionaries
Assuming method names without checking docs
Ignoring variable definitions

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More LangChain Quizzes

You wrote this code to create evaluation examples but get an error:

Step 1: Check example dictionary keys

Step 2: Identify mismatch causing error

Final Answer:

Quick Check:

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