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e31705b5ab
when the LLMs output 'yes|no'，BooleanOutputParser can parse it to 'True|False', fix the ValueError in parse(). <!-- when use the BooleanOutputParser in the chain_filter.py, the LLMs output 'yes|no'，the function 'parse' will throw ValueError。 --> Fixes # (issue) #5396 https://github.com/hwchase17/langchain/issues/5396 --------- Co-authored-by: gaofeng27692 <gaofeng27692@hundsun.com>
30 lines
892 B
Python
30 lines
892 B
Python
from langchain.schema import BaseOutputParser
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class BooleanOutputParser(BaseOutputParser[bool]):
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true_val: str = "YES"
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false_val: str = "NO"
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def parse(self, text: str) -> bool:
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"""Parse the output of an LLM call to a boolean.
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Args:
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text: output of language model
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Returns:
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boolean
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"""
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cleaned_text = text.strip()
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if cleaned_text.upper() not in (self.true_val.upper(), self.false_val.upper()):
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raise ValueError(
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f"BooleanOutputParser expected output value to either be "
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f"{self.true_val} or {self.false_val}. Received {cleaned_text}."
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)
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return cleaned_text.upper() == self.true_val.upper()
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@property
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def _type(self) -> str:
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"""Snake-case string identifier for output parser type."""
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return "boolean_output_parser"
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