app.py

import gradio as gr
import torch
import transformers
from transformers import AutoTokenizer
from langchain import LLMChain, HuggingFacePipeline, PromptTemplate

def greet(text):

    model = "meta-llama/Llama-2-7b-chat-hf"
    tokenizer = AutoTokenizer.from_pretrained(model)
    
    pipeline = transformers.pipeline(
    "text-generation",
    model=model,
    tokenizer=tokenizer,
    torch_dtype=torch.bfloat16,
    trust_remote_code=True,
    device_map="auto",
    max_length=1000,
    do_sample=True,
    top_k=10,
    num_return_sequences=1,
    eos_token_id=tokenizer.eos_token_id
    )

    llm = HuggingFacePipeline(pipeline = pipeline, model_kwargs = {'temperature':0})

    template = """
              Write a summary of the following text delimited by triple backticks.
              Return your response which covers the key points of the text.
              ```{text}```
              SUMMARY:
               """
    
    prompt = PromptTemplate(template=template, input_variables=["text"])
    llm_chain = LLMChain(prompt=prompt, llm=llm)

    summary = llm_chain.run(text)
    
    return summary

with gr.Blocks() as demo:
    
    text = gr.Textbox(label="Text")
    summary = gr.Textbox(label="Summary")
    greet_btn = gr.Button("Submit")
    greet_btn.click(fn=greet, inputs=text, outputs=summary, api_name="greet")

demo.launch()