Chat Format

This is a lightweight Python library for formatting chat prompts for various open source LLMs.

from chatformat import format_chat_prompt

prompt, stop = format_chat_prompt(
	template='vicuna',
	messages=[
		{'role': 'system', 'content': 'You are a very clever LLM.'},
		{'role': 'user', 'content': 'Hello?'}
	]
)

will yield the following prompt:

You are a very clever LLM.

USER: Hello?
ASSISTANT: 

The stop variable should be used as stopping criteria in your LLM's implementation.

Install

pip install chatformat

Supported Formats

Run the test.py script to see all formats in action.

Llama-2

<s>[INST] <<SYS>>
{system_message}
<</SYS>>

{user_message} [/INST] {model_reply}</s><s>[INST] {user_message} [/INST] {model_reply}</s>

Alpaca

{system_message}

### Instruction:
{user_message}

### Response:
{model_reply}

Vicuna

A chat between a curious user and an artificial intelligence assistant. The assistant gives helpful, detailed, and polite answers to the user's questions.

USER: Hello!
ASSISTANT: Hello!</s>
USER: How are you?
ASSISTANT: I am good.</s>

ChatLM

<|im_start|>system
You are ChatGPT, a large language model trained by OpenAI. Answer as concisely as possible.
Knowledge cutoff: 2021-09-01
Current date: 2023-03-01<|im_end|>
<|im_start|>user
How are you?<|im_end|>
<|im_start|>assistant
I am doing well!<|im_end|>

Custom Formats

You can pass a dictionary as template to format_chat_prompt, which describes your custom format.

from chatformat import format_chat_prompt

prompt, stop = format_chat_prompt(
	template={
		'with_system': (
			'>system: {system}\n'
			'>user: {user}\n'
			'>assistant: {assistant}'
			'</s>'
		),
		'without_system': (
			'>user: {user}\n'
			'>assistant: {assistant}'
			'</s>'
		),
		'round_seperator': '\n'
	},
	messages=[
		{'role': 'system', 'content': 'You are a very clever LLM.'},
		{'role': 'user', 'content': 'Hello?'}
	]
)

The custom template dictionary shall be structured as follows

Key	Purpose
with_system	Defines the first round if a system prompt is set.
without_system	Defines consecutive rounds, and/or first if no system prompt is set.
round_seperator	Defines how to join multiple rounds.
stop	Defines the stopword(s) to prevent self-talk. Can be an array. If not set, will be derived from any text following {assistant}.

Take a look at templates.yml for examples.