python[patch]: accept simple evaluators

[baskaryan]

can write evaluators like this:

from langsmith import evaluate

def simp(inputs: dict, outputs: dict, reference_outputs: dict) -> dict:
    return {"results": [
        {"score": inputs == outputs, "key": 'identity'}, 
        {"score": outputs == reference_outputs, "key": "correct"}
    ]}

evaluate(
    (lambda x: x),
    data="Sample Dataset 3",
    evaluators=[simp],
)

example experiment: left-tray-86 https://dev.smith.langchain.com/public/e7782ea0-3de5-4352-8cd4-7b2cdbb03e4c/d

[hinthornw]

Nice i like the start will re-review this morning

[hinthornw]

nit

[jakerachleff]

might be nice to add like a couple unit tests on this to make it obvious it's working

[jakerachleff]

I think this makes sense, but would add some extra tests in to confirm it works properly

[jakerachleff]

Do we want to add debug logs letting you know what function type is being used? Might be helpful since we tell people to enable debug logs for debugging issues in the SDK?

[hinthornw]

Do we want it to be like pytest where it's all by name?
run, example, inputs, predictions, reference

[baskaryan]

Do we want it to be like pytest where it's all by name? run, example, inputs, predictions, reference

yea i like that. for backwards compat can't enforce run/example but can enforce the others