Complete the code to import the LangChain retriever class.
from langchain.vectorstores import [1]
The Chroma class is used as a vector store retriever in LangChain for RAG.
Complete the code to initialize the retriever with the vector store.
retriever = [1](embedding_function=embeddings, persist_directory='db')
Chroma is the vector store class used to create a retriever instance in LangChain.
Fix the error in the code to enable source citation in the RAG chain.
qa_chain = RetrievalQAWithSourcesChain(llm=llm, retriever=[1], return_source_documents=True)
The retriever should be passed as an object, not called as a function.
Fill both blanks to extract answer and sources from the RAG output.
answer = result[[1]] sources = result[[2]]
The RAG output dictionary contains the 'answer' key for the answer text and 'source_documents' key for the source documents.
Fill all three blanks to create a dictionary of source texts from documents.
source_texts = [1](doc.page_content for doc in [2]) source_dict = {i: text for i, text in [3](source_texts)}
We first create a list of page contents from source documents, then use enumerate to pair indices with texts for the dictionary comprehension.