mirror of
https://github.com/hwchase17/langchain
synced 2024-11-04 06:00:26 +00:00
60 lines
1.3 KiB
Python
60 lines
1.3 KiB
Python
from langchain.utilities import DuckDuckGoSearchAPIWrapper
|
||
from langchain_community.chat_models import ChatOpenAI
|
||
from langchain_core.output_parsers import StrOutputParser
|
||
from langchain_core.prompts import ChatPromptTemplate
|
||
from langchain_core.pydantic_v1 import BaseModel
|
||
from langchain_core.runnables import RunnablePassthrough
|
||
|
||
template = """Answer the users question based only on the following context:
|
||
|
||
<context>
|
||
{context}
|
||
</context>
|
||
|
||
Question: {question}
|
||
"""
|
||
prompt = ChatPromptTemplate.from_template(template)
|
||
|
||
model = ChatOpenAI(temperature=0)
|
||
|
||
search = DuckDuckGoSearchAPIWrapper()
|
||
|
||
|
||
def retriever(query):
|
||
return search.run(query)
|
||
|
||
|
||
template = """Provide a better search query for \
|
||
web search engine to answer the given question, end \
|
||
the queries with ’**’. Question: \
|
||
{x} Answer:"""
|
||
rewrite_prompt = ChatPromptTemplate.from_template(template)
|
||
|
||
# Parser to remove the `**`
|
||
|
||
|
||
def _parse(text):
|
||
return text.strip("**")
|
||
|
||
|
||
rewriter = rewrite_prompt | ChatOpenAI(temperature=0) | StrOutputParser() | _parse
|
||
|
||
chain = (
|
||
{
|
||
"context": {"x": RunnablePassthrough()} | rewriter | retriever,
|
||
"question": RunnablePassthrough(),
|
||
}
|
||
| prompt
|
||
| model
|
||
| StrOutputParser()
|
||
)
|
||
|
||
# Add input type for playground
|
||
|
||
|
||
class Question(BaseModel):
|
||
__root__: str
|
||
|
||
|
||
chain = chain.with_types(input_type=Question)
|