langchain

064a1db2 - [Documentation] Show how to initiate pinecone from an existing index (#3070)

[Documentation] Show how to initiate pinecone from an existing index (#3070) ## What is this PR for: * This PR adds a commented line of code in the documentation that shows how someone can use the Pinecone client with an already existing Pinecone index * The documentation currently only shows how to create a pinecone index from langchain documents but not how to load one that already exists