langchain/libs/experimental/tests
Martin Krasser 79ed66f870
EXPERIMENTAL Generic LLM wrapper to support chat model interface with configurable chat prompt format (#8295)
## Update 2023-09-08

This PR now supports further models in addition to Lllama-2 chat models.
See [this comment](#issuecomment-1668988543) for further details. The
title of this PR has been updated accordingly.

## Original PR description

This PR adds a generic `Llama2Chat` model, a wrapper for LLMs able to
serve Llama-2 chat models (like `LlamaCPP`,
`HuggingFaceTextGenInference`, ...). It implements `BaseChatModel`,
converts a list of chat messages into the [required Llama-2 chat prompt
format](https://huggingface.co/blog/llama2#how-to-prompt-llama-2) and
forwards the formatted prompt as `str` to the wrapped `LLM`. Usage
example:

```python
# uses a locally hosted Llama2 chat model
llm = HuggingFaceTextGenInference(
    inference_server_url="http://127.0.0.1:8080/",
    max_new_tokens=512,
    top_k=50,
    temperature=0.1,
    repetition_penalty=1.03,
)

# Wrap llm to support Llama2 chat prompt format.
# Resulting model is a chat model
model = Llama2Chat(llm=llm)

messages = [
    SystemMessage(content="You are a helpful assistant."),
    MessagesPlaceholder(variable_name="chat_history"),
    HumanMessagePromptTemplate.from_template("{text}"),
]

prompt = ChatPromptTemplate.from_messages(messages)
memory = ConversationBufferMemory(memory_key="chat_history", return_messages=True)
chain = LLMChain(llm=model, prompt=prompt, memory=memory)

# use chat model in a conversation
# ...
```

Also part of this PR are tests and a demo notebook.

- Tag maintainer: @hwchase17
- Twitter handle: `@mrt1nz`

---------

Co-authored-by: Erick Friis <erick@langchain.dev>
2023-11-17 16:32:13 -08:00
..
integration_tests Add CI check that integration tests compile (#12090) 2023-10-21 10:52:18 -04:00
unit_tests EXPERIMENTAL Generic LLM wrapper to support chat model interface with configurable chat prompt format (#8295) 2023-11-17 16:32:13 -08:00
__init__.py Harrison/move experimental (#8084) 2023-07-21 10:36:28 -07:00