Source code for langchain.chains.prompt_selector
from abc import ABC, abstractmethod
from typing import Callable, List, Tuple
from langchain_core.language_models import BaseLanguageModel
from langchain_core.language_models.chat_models import BaseChatModel
from langchain_core.language_models.llms import BaseLLM
from langchain_core.prompts import BasePromptTemplate
from langchain_core.pydantic_v1 import BaseModel, Field
[docs]class BasePromptSelector(BaseModel, ABC):
"""Base class for prompt selectors."""
[docs] @abstractmethod
def get_prompt(self, llm: BaseLanguageModel) -> BasePromptTemplate:
"""Get default prompt for a language model."""
[docs]class ConditionalPromptSelector(BasePromptSelector):
"""Prompt collection that goes through conditionals."""
default_prompt: BasePromptTemplate
"""Default prompt to use if no conditionals match."""
conditionals: List[
Tuple[Callable[[BaseLanguageModel], bool], BasePromptTemplate]
] = Field(default_factory=list)
"""List of conditionals and prompts to use if the conditionals match."""
[docs] def get_prompt(self, llm: BaseLanguageModel) -> BasePromptTemplate:
"""Get default prompt for a language model.
Args:
llm: Language model to get prompt for.
Returns:
Prompt to use for the language model.
"""
for condition, prompt in self.conditionals:
if condition(llm):
return prompt
return self.default_prompt
[docs]def is_llm(llm: BaseLanguageModel) -> bool:
"""Check if the language model is a LLM.
Args:
llm: Language model to check.
Returns:
True if the language model is a BaseLLM model, False otherwise.
"""
return isinstance(llm, BaseLLM)
[docs]def is_chat_model(llm: BaseLanguageModel) -> bool:
"""Check if the language model is a chat model.
Args:
llm: Language model to check.
Returns:
True if the language model is a BaseChatModel model, False otherwise.
"""
return isinstance(llm, BaseChatModel)