LightRAG/lightrag/llm.py

import os
import copy
from functools import lru_cache
import json
import aioboto3
import aiohttp
import numpy as np
import ollama

from openai import (
    AsyncOpenAI,
    APIConnectionError,
    RateLimitError,
    Timeout,
    AsyncAzureOpenAI,
)

import base64
import struct

from tenacity import (
    retry,
    stop_after_attempt,
    wait_exponential,
    retry_if_exception_type,
)
from transformers import AutoTokenizer, AutoModelForCausalLM
import torch
from pydantic import BaseModel, Field
from typing import List, Dict, Callable, Any
from .base import BaseKVStorage
from .utils import compute_args_hash, wrap_embedding_func_with_attrs

os.environ["TOKENIZERS_PARALLELISM"] = "false"


@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=10),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),
)
async def openai_complete_if_cache(
    model,
    prompt,
    system_prompt=None,
    history_messages=[],
    base_url=None,
    api_key=None,
    **kwargs,
) -> str:
    if api_key:
        os.environ["OPENAI_API_KEY"] = api_key

    openai_async_client = (
        AsyncOpenAI() if base_url is None else AsyncOpenAI(base_url=base_url)
    )
    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    messages = []
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})
    messages.extend(history_messages)
    messages.append({"role": "user", "content": prompt})
    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]

    response = await openai_async_client.chat.completions.create(
        model=model, messages=messages, **kwargs
    )

    if hashing_kv is not None:
        await hashing_kv.upsert(
            {args_hash: {"return": response.choices[0].message.content, "model": model}}
        )
    return response.choices[0].message.content


@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=10),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),
)
async def azure_openai_complete_if_cache(
    model,
    prompt,
    system_prompt=None,
    history_messages=[],
    base_url=None,
    api_key=None,
    **kwargs,
):
    if api_key:
        os.environ["AZURE_OPENAI_API_KEY"] = api_key
    if base_url:
        os.environ["AZURE_OPENAI_ENDPOINT"] = base_url

    openai_async_client = AsyncAzureOpenAI(
        azure_endpoint=os.getenv("AZURE_OPENAI_ENDPOINT"),
        api_key=os.getenv("AZURE_OPENAI_API_KEY"),
        api_version=os.getenv("AZURE_OPENAI_API_VERSION"),
    )

    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    messages = []
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})
    messages.extend(history_messages)
    if prompt is not None:
        messages.append({"role": "user", "content": prompt})
    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]

    response = await openai_async_client.chat.completions.create(
        model=model, messages=messages, **kwargs
    )

    if hashing_kv is not None:
        await hashing_kv.upsert(
            {args_hash: {"return": response.choices[0].message.content, "model": model}}
        )
    return response.choices[0].message.content


class BedrockError(Exception):
    """Generic error for issues related to Amazon Bedrock"""


@retry(
    stop=stop_after_attempt(5),
    wait=wait_exponential(multiplier=1, max=60),
    retry=retry_if_exception_type((BedrockError)),
)
async def bedrock_complete_if_cache(
    model,
    prompt,
    system_prompt=None,
    history_messages=[],
    aws_access_key_id=None,
    aws_secret_access_key=None,
    aws_session_token=None,
    **kwargs,
) -> str:
    os.environ["AWS_ACCESS_KEY_ID"] = os.environ.get(
        "AWS_ACCESS_KEY_ID", aws_access_key_id
    )
    os.environ["AWS_SECRET_ACCESS_KEY"] = os.environ.get(
        "AWS_SECRET_ACCESS_KEY", aws_secret_access_key
    )
    os.environ["AWS_SESSION_TOKEN"] = os.environ.get(
        "AWS_SESSION_TOKEN", aws_session_token
    )

    # Fix message history format
    messages = []
    for history_message in history_messages:
        message = copy.copy(history_message)
        message["content"] = [{"text": message["content"]}]
        messages.append(message)

    # Add user prompt
    messages.append({"role": "user", "content": [{"text": prompt}]})

    # Initialize Converse API arguments
    args = {"modelId": model, "messages": messages}

    # Define system prompt
    if system_prompt:
        args["system"] = [{"text": system_prompt}]

    # Map and set up inference parameters
    inference_params_map = {
        "max_tokens": "maxTokens",
        "top_p": "topP",
        "stop_sequences": "stopSequences",
    }
    if inference_params := list(
        set(kwargs) & set(["max_tokens", "temperature", "top_p", "stop_sequences"])
    ):
        args["inferenceConfig"] = {}
        for param in inference_params:
            args["inferenceConfig"][inference_params_map.get(param, param)] = (
                kwargs.pop(param)
            )

    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]

    # Call model via Converse API
    session = aioboto3.Session()
    async with session.client("bedrock-runtime") as bedrock_async_client:
        try:
            response = await bedrock_async_client.converse(**args, **kwargs)
        except Exception as e:
            raise BedrockError(e)

        if hashing_kv is not None:
            await hashing_kv.upsert(
                {
                    args_hash: {
                        "return": response["output"]["message"]["content"][0]["text"],
                        "model": model,
                    }
                }
            )

        return response["output"]["message"]["content"][0]["text"]


@lru_cache(maxsize=1)
def initialize_hf_model(model_name):
    hf_tokenizer = AutoTokenizer.from_pretrained(
        model_name, device_map="auto", trust_remote_code=True
    )
    hf_model = AutoModelForCausalLM.from_pretrained(
        model_name, device_map="auto", trust_remote_code=True
    )
    if hf_tokenizer.pad_token is None:
        hf_tokenizer.pad_token = hf_tokenizer.eos_token

    return hf_model, hf_tokenizer


async def hf_model_if_cache(
    model, prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    model_name = model
    hf_model, hf_tokenizer = initialize_hf_model(model_name)
    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    messages = []
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})
    messages.extend(history_messages)
    messages.append({"role": "user", "content": prompt})

    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]
    input_prompt = ""
    try:
        input_prompt = hf_tokenizer.apply_chat_template(
            messages, tokenize=False, add_generation_prompt=True
        )
    except Exception:
        try:
            ori_message = copy.deepcopy(messages)
            if messages[0]["role"] == "system":
                messages[1]["content"] = (
                    "<system>"
                    + messages[0]["content"]
                    + "</system>\n"
                    + messages[1]["content"]
                )
                messages = messages[1:]
                input_prompt = hf_tokenizer.apply_chat_template(
                    messages, tokenize=False, add_generation_prompt=True
                )
        except Exception:
            len_message = len(ori_message)
            for msgid in range(len_message):
                input_prompt = (
                    input_prompt
                    + "<"
                    + ori_message[msgid]["role"]
                    + ">"
                    + ori_message[msgid]["content"]
                    + "</"
                    + ori_message[msgid]["role"]
                    + ">\n"
                )

    input_ids = hf_tokenizer(
        input_prompt, return_tensors="pt", padding=True, truncation=True
    ).to("cuda")
    inputs = {k: v.to(hf_model.device) for k, v in input_ids.items()}
    output = hf_model.generate(
        **input_ids, max_new_tokens=512, num_return_sequences=1, early_stopping=True
    )
    response_text = hf_tokenizer.decode(
        output[0][len(inputs["input_ids"][0]) :], skip_special_tokens=True
    )
    if hashing_kv is not None:
        await hashing_kv.upsert({args_hash: {"return": response_text, "model": model}})
    return response_text


async def ollama_model_if_cache(
    model, prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    kwargs.pop("max_tokens", None)
    kwargs.pop("response_format", None)
    host = kwargs.pop("host", None)
    timeout = kwargs.pop("timeout", None)

    ollama_client = ollama.AsyncClient(host=host, timeout=timeout)
    messages = []
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})

    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    messages.extend(history_messages)
    messages.append({"role": "user", "content": prompt})
    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]

    response = await ollama_client.chat(model=model, messages=messages, **kwargs)

    result = response["message"]["content"]

    if hashing_kv is not None:
        await hashing_kv.upsert({args_hash: {"return": result, "model": model}})

    return result


@lru_cache(maxsize=1)
def initialize_lmdeploy_pipeline(
    model,
    tp=1,
    chat_template=None,
    log_level="WARNING",
    model_format="hf",
    quant_policy=0,
):
    from lmdeploy import pipeline, ChatTemplateConfig, TurbomindEngineConfig

    lmdeploy_pipe = pipeline(
        model_path=model,
        backend_config=TurbomindEngineConfig(
            tp=tp, model_format=model_format, quant_policy=quant_policy
        ),
        chat_template_config=ChatTemplateConfig(model_name=chat_template)
        if chat_template
        else None,
        log_level="WARNING",
    )
    return lmdeploy_pipe


async def lmdeploy_model_if_cache(
    model,
    prompt,
    system_prompt=None,
    history_messages=[],
    chat_template=None,
    model_format="hf",
    quant_policy=0,
    **kwargs,
) -> str:
    """
    Args:
        model (str): The path to the model.
            It could be one of the following options:
                    - i) A local directory path of a turbomind model which is
                        converted by `lmdeploy convert` command or download
                        from ii) and iii).
                    - ii) The model_id of a lmdeploy-quantized model hosted
                        inside a model repo on huggingface.co, such as
                        "InternLM/internlm-chat-20b-4bit",
                        "lmdeploy/llama2-chat-70b-4bit", etc.
                    - iii) The model_id of a model hosted inside a model repo
                        on huggingface.co, such as "internlm/internlm-chat-7b",
                        "Qwen/Qwen-7B-Chat ", "baichuan-inc/Baichuan2-7B-Chat"
                        and so on.
        chat_template (str): needed when model is a pytorch model on
            huggingface.co, such as "internlm-chat-7b",
            "Qwen-7B-Chat ", "Baichuan2-7B-Chat" and so on,
            and when the model name of local path did not match the original model name in HF.
        tp (int): tensor parallel
        prompt (Union[str, List[str]]): input texts to be completed.
        do_preprocess (bool): whether pre-process the messages. Default to
            True, which means chat_template will be applied.
        skip_special_tokens (bool): Whether or not to remove special tokens
            in the decoding. Default to be True.
        do_sample (bool): Whether or not to use sampling, use greedy decoding otherwise.
            Default to be False, which means greedy decoding will be applied.
    """
    try:
        import lmdeploy
        from lmdeploy import version_info, GenerationConfig
    except Exception:
        raise ImportError("Please install lmdeploy before intialize lmdeploy backend.")

    kwargs.pop("response_format", None)
    max_new_tokens = kwargs.pop("max_tokens", 512)
    tp = kwargs.pop("tp", 1)
    skip_special_tokens = kwargs.pop("skip_special_tokens", True)
    do_preprocess = kwargs.pop("do_preprocess", True)
    do_sample = kwargs.pop("do_sample", False)
    gen_params = kwargs

    version = version_info
    if do_sample is not None and version < (0, 6, 0):
        raise RuntimeError(
            "`do_sample` parameter is not supported by lmdeploy until "
            f"v0.6.0, but currently using lmdeloy {lmdeploy.__version__}"
        )
    else:
        do_sample = True
        gen_params.update(do_sample=do_sample)

    lmdeploy_pipe = initialize_lmdeploy_pipeline(
        model=model,
        tp=tp,
        chat_template=chat_template,
        model_format=model_format,
        quant_policy=quant_policy,
        log_level="WARNING",
    )

    messages = []
    if system_prompt:
        messages.append({"role": "system", "content": system_prompt})

    hashing_kv: BaseKVStorage = kwargs.pop("hashing_kv", None)
    messages.extend(history_messages)
    messages.append({"role": "user", "content": prompt})
    if hashing_kv is not None:
        args_hash = compute_args_hash(model, messages)
        if_cache_return = await hashing_kv.get_by_id(args_hash)
        if if_cache_return is not None:
            return if_cache_return["return"]

    gen_config = GenerationConfig(
        skip_special_tokens=skip_special_tokens,
        max_new_tokens=max_new_tokens,
        **gen_params,
    )

    response = ""
    async for res in lmdeploy_pipe.generate(
        messages,
        gen_config=gen_config,
        do_preprocess=do_preprocess,
        stream_response=False,
        session_id=1,
    ):
        response += res.response

    if hashing_kv is not None:
        await hashing_kv.upsert({args_hash: {"return": response, "model": model}})
    return response


async def gpt_4o_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    return await openai_complete_if_cache(
        "gpt-4o",
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


async def gpt_4o_mini_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    return await openai_complete_if_cache(
        "gpt-4o-mini",
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


async def azure_openai_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    return await azure_openai_complete_if_cache(
        "conversation-4o-mini",
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


async def bedrock_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    return await bedrock_complete_if_cache(
        "anthropic.claude-3-haiku-20240307-v1:0",
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


async def hf_model_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    model_name = kwargs["hashing_kv"].global_config["llm_model_name"]
    return await hf_model_if_cache(
        model_name,
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


async def ollama_model_complete(
    prompt, system_prompt=None, history_messages=[], **kwargs
) -> str:
    model_name = kwargs["hashing_kv"].global_config["llm_model_name"]
    return await ollama_model_if_cache(
        model_name,
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        **kwargs,
    )


@wrap_embedding_func_with_attrs(embedding_dim=1536, max_token_size=8192)
@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=60),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),
)
async def openai_embedding(
    texts: list[str],
    model: str = "text-embedding-3-small",
    base_url: str = None,
    api_key: str = None,
) -> np.ndarray:
    if api_key:
        os.environ["OPENAI_API_KEY"] = api_key

    openai_async_client = (
        AsyncOpenAI() if base_url is None else AsyncOpenAI(base_url=base_url)
    )
    response = await openai_async_client.embeddings.create(
        model=model, input=texts, encoding_format="float"
    )
    return np.array([dp.embedding for dp in response.data])


@wrap_embedding_func_with_attrs(embedding_dim=1536, max_token_size=8192)
@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=10),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),
)
async def azure_openai_embedding(
    texts: list[str],
    model: str = "text-embedding-3-small",
    base_url: str = None,
    api_key: str = None,
) -> np.ndarray:
    if api_key:
        os.environ["AZURE_OPENAI_API_KEY"] = api_key
    if base_url:
        os.environ["AZURE_OPENAI_ENDPOINT"] = base_url

    openai_async_client = AsyncAzureOpenAI(
        azure_endpoint=os.getenv("AZURE_OPENAI_ENDPOINT"),
        api_key=os.getenv("AZURE_OPENAI_API_KEY"),
        api_version=os.getenv("AZURE_OPENAI_API_VERSION"),
    )

    response = await openai_async_client.embeddings.create(
        model=model, input=texts, encoding_format="float"
    )
    return np.array([dp.embedding for dp in response.data])


@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=60),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),
)
async def siliconcloud_embedding(
    texts: list[str],
    model: str = "netease-youdao/bce-embedding-base_v1",
    base_url: str = "https://api.siliconflow.cn/v1/embeddings",
    max_token_size: int = 512,
    api_key: str = None,
) -> np.ndarray:
    if api_key and not api_key.startswith("Bearer "):
        api_key = "Bearer " + api_key

    headers = {"Authorization": api_key, "Content-Type": "application/json"}

    truncate_texts = [text[0:max_token_size] for text in texts]

    payload = {"model": model, "input": truncate_texts, "encoding_format": "base64"}

    base64_strings = []
    async with aiohttp.ClientSession() as session:
        async with session.post(base_url, headers=headers, json=payload) as response:
            content = await response.json()
            if "code" in content:
                raise ValueError(content)
            base64_strings = [item["embedding"] for item in content["data"]]

    embeddings = []
    for string in base64_strings:
        decode_bytes = base64.b64decode(string)
        n = len(decode_bytes) // 4
        float_array = struct.unpack("<" + "f" * n, decode_bytes)
        embeddings.append(float_array)
    return np.array(embeddings)


# @wrap_embedding_func_with_attrs(embedding_dim=1024, max_token_size=8192)
# @retry(
#     stop=stop_after_attempt(3),
#     wait=wait_exponential(multiplier=1, min=4, max=10),
#     retry=retry_if_exception_type((RateLimitError, APIConnectionError, Timeout)),  # TODO: fix exceptions
# )
async def bedrock_embedding(
    texts: list[str],
    model: str = "amazon.titan-embed-text-v2:0",
    aws_access_key_id=None,
    aws_secret_access_key=None,
    aws_session_token=None,
) -> np.ndarray:
    os.environ["AWS_ACCESS_KEY_ID"] = os.environ.get(
        "AWS_ACCESS_KEY_ID", aws_access_key_id
    )
    os.environ["AWS_SECRET_ACCESS_KEY"] = os.environ.get(
        "AWS_SECRET_ACCESS_KEY", aws_secret_access_key
    )
    os.environ["AWS_SESSION_TOKEN"] = os.environ.get(
        "AWS_SESSION_TOKEN", aws_session_token
    )

    session = aioboto3.Session()
    async with session.client("bedrock-runtime") as bedrock_async_client:
        if (model_provider := model.split(".")[0]) == "amazon":
            embed_texts = []
            for text in texts:
                if "v2" in model:
                    body = json.dumps(
                        {
                            "inputText": text,
                            # 'dimensions': embedding_dim,
                            "embeddingTypes": ["float"],
                        }
                    )
                elif "v1" in model:
                    body = json.dumps({"inputText": text})
                else:
                    raise ValueError(f"Model {model} is not supported!")

                response = await bedrock_async_client.invoke_model(
                    modelId=model,
                    body=body,
                    accept="application/json",
                    contentType="application/json",
                )

                response_body = await response.get("body").json()

                embed_texts.append(response_body["embedding"])
        elif model_provider == "cohere":
            body = json.dumps(
                {"texts": texts, "input_type": "search_document", "truncate": "NONE"}
            )

            response = await bedrock_async_client.invoke_model(
                model=model,
                body=body,
                accept="application/json",
                contentType="application/json",
            )

            response_body = json.loads(response.get("body").read())

            embed_texts = response_body["embeddings"]
        else:
            raise ValueError(f"Model provider '{model_provider}' is not supported!")

        return np.array(embed_texts)


async def hf_embedding(texts: list[str], tokenizer, embed_model) -> np.ndarray:
    device = next(embed_model.parameters()).device
    input_ids = tokenizer(
        texts, return_tensors="pt", padding=True, truncation=True
    ).input_ids.to(device)
    with torch.no_grad():
        outputs = embed_model(input_ids)
        embeddings = outputs.last_hidden_state.mean(dim=1)
    if embeddings.dtype == torch.bfloat16:
        return embeddings.detach().to(torch.float32).cpu().numpy()
    else:
        return embeddings.detach().cpu().numpy()


async def ollama_embedding(texts: list[str], embed_model, **kwargs) -> np.ndarray:
    embed_text = []
    ollama_client = ollama.Client(**kwargs)
    for text in texts:
        data = ollama_client.embeddings(model=embed_model, prompt=text)
        embed_text.append(data["embedding"])

    return embed_text


class Model(BaseModel):
    """
    This is a Pydantic model class named 'Model' that is used to define a custom language model.

    Attributes:
        gen_func (Callable[[Any], str]): A callable function that generates the response from the language model.
            The function should take any argument and return a string.
        kwargs (Dict[str, Any]): A dictionary that contains the arguments to pass to the callable function.
            This could include parameters such as the model name, API key, etc.

    Example usage:
        Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_1"]})

    In this example, 'openai_complete_if_cache' is the callable function that generates the response from the OpenAI model.
    The 'kwargs' dictionary contains the model name and API key to be passed to the function.
    """

    gen_func: Callable[[Any], str] = Field(
        ...,
        description="A function that generates the response from the llm. The response must be a string",
    )
    kwargs: Dict[str, Any] = Field(
        ...,
        description="The arguments to pass to the callable function. Eg. the api key, model name, etc",
    )

    class Config:
        arbitrary_types_allowed = True


class MultiModel:
    """
    Distributes the load across multiple language models. Useful for circumventing low rate limits with certain api providers especially if you are on the free tier.
    Could also be used for spliting across diffrent models or providers.

    Attributes:
        models (List[Model]): A list of language models to be used.

    Usage example:
        ```python
        models = [
            Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_1"]}),
            Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_2"]}),
            Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_3"]}),
            Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_4"]}),
            Model(gen_func=openai_complete_if_cache, kwargs={"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY_5"]}),
        ]
        multi_model = MultiModel(models)
        rag = LightRAG(
            llm_model_func=multi_model.llm_model_func
            / ..other args
            )
        ```
    """

    def __init__(self, models: List[Model]):
        self._models = models
        self._current_model = 0

    def _next_model(self):
        self._current_model = (self._current_model + 1) % len(self._models)
        return self._models[self._current_model]

    async def llm_model_func(
        self, prompt, system_prompt=None, history_messages=[], **kwargs
    ) -> str:
        kwargs.pop("model", None)  # stop from overwriting the custom model name
        next_model = self._next_model()
        args = dict(
            prompt=prompt,
            system_prompt=system_prompt,
            history_messages=history_messages,
            **kwargs,
            **next_model.kwargs,
        )

        return await next_model.gen_func(**args)


if __name__ == "__main__":
    import asyncio

    async def main():
        result = await gpt_4o_mini_complete("How are you?")
        print(result)

    asyncio.run(main())