Banana provided serverless GPU inference for AI models, a CI/CD build pipeline and a simple Python framework (Potassium) to server your models.
This page covers how to use the Banana ecosystem within LangChain.

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Installation and Setup

  • Install the python package banana-dev:
pip install banana-dev
  • Get an Banana api key from the Banana.dev dashboard and set it as an environment variable (BANANA_API_KEY)
  • Get your model’s key and url slug from the model’s details page.

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Define your Banana Template

You’ll need to set up a Github repo for your Banana app. You can get started in 5 minutes using this guide. Alternatively, for a ready-to-go LLM example, you can check out Banana’s CodeLlama-7B-Instruct-GPTQ GitHub repository. Just fork it and deploy it within Banana. Other starter repos are available here.

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Build the Banana app

To use Banana apps within Langchain, you must include the outputs key in the returned json, and the value must be a string. 
# Return the results as a dictionary
result = {'outputs': result}
An example inference function would be: 
@app.handler("/")
def handler(context: dict, request: Request) -> Response:
    """Handle a request to generate code from a prompt."""
    model = context.get("model")
    tokenizer = context.get("tokenizer")
    max_new_tokens = request.json.get("max_new_tokens", 512)
    temperature = request.json.get("temperature", 0.7)
    prompt = request.json.get("prompt")
    prompt_template=f'''[INST] Write code to solve the following coding problem that obeys the constraints and passes the example test cases. Please wrap your code answer using ```:
    {prompt}
    [/INST]
    '''
    input_ids = tokenizer(prompt_template, return_tensors='pt').input_ids.cuda()
    output = model.generate(inputs=input_ids, temperature=temperature, max_new_tokens=max_new_tokens)
    result = tokenizer.decode(output[0])
    return Response(json={"outputs": result}, status=200)
This example is from the app.py file in CodeLlama-7B-Instruct-GPTQ.

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LLM

from langchain_community.llms import Banana
See a usage example.