LangChain-07 Multiple Chains 多链串联_langchain中把几个chain串起来

Runnables can easily be used to string together multiple Chains
Runnables 可以很容易地用于将多个链串在一起

安装依赖

pip install --upgrade --quiet  langchain-core langchain-community langchain-openai
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编写代码

from operator import itemgetter

from langchain_core.output_parsers import StrOutputParser
from langchain_core.prompts import ChatPromptTemplate
from langchain_openai import ChatOpenAI

prompt1 = ChatPromptTemplate.from_template("what is the city {person} is from?")
prompt2 = ChatPromptTemplate.from_template(
    "what country is the city {city} in? respond in {language}"
)

model = ChatOpenAI(
    model="gpt-3.5-turbo",
)

chain1 = prompt1 | model | StrOutputParser()

chain2 = (
    {"city": chain1, "language": itemgetter("language")}
    | prompt2
    | model
    | StrOutputParser()
)

message = chain2.invoke({"person": "obama", "language": "spanish"})
print(f"message: {message}")

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观察代码

chain1 = prompt1 | model | StrOutputParser()

chain2 = (
    {"city": chain1, "language": itemgetter("language")}
    | prompt2
    | model
    | StrOutputParser()
)
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我们可以发现， chian1 和 chian2 可以很方便的串联在一起，方便我们进行扩展。

运行结果

➜ python3 test07.py
message: Chicago, Illinois, se encuentra en los Estados Unidos.
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