Source code for langchain.output_parsers.enum

from enum import Enum
from typing import Any, Dict, List, Type

from langchain_core.exceptions import OutputParserException
from langchain_core.output_parsers import BaseOutputParser
from langchain_core.pydantic_v1 import root_validator

[docs]class EnumOutputParser(BaseOutputParser): """Parse an output that is one of a set of values.""" enum: Type[Enum] """The enum to parse. Its values must be strings.""" @root_validator() def raise_deprecation(cls, values: Dict) -> Dict: enum = values["enum"] if not all(isinstance(e.value, str) for e in enum): raise ValueError("Enum values must be strings") return values @property def _valid_values(self) -> List[str]: return [e.value for e in self.enum]
[docs] def parse(self, response: str) -> Any: try: return self.enum(response.strip()) except ValueError: raise OutputParserException( f"Response '{response}' is not one of the " f"expected values: {self._valid_values}" )
[docs] def get_format_instructions(self) -> str: return f"Select one of the following options: {', '.join(self._valid_values)}"