app.py

#https://python.langchain.com/docs/how_to/parallel/
import gradio as gr
from langchain_openai import ChatOpenAI
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.runnables import RunnableParallel

def process_parallel(topic, api_key):
    try:
        # Initialize the model
        model = ChatOpenAI(
            openai_api_key=api_key,
            model="gpt-4o-mini",
            temperature=0.7
        )
        
        # Create two chains
        joke_chain = ChatPromptTemplate.from_template("tell me a joke about {topic}") | model
        poem_chain = ChatPromptTemplate.from_template("write a 2-line poem about {topic}") | model
        
        # Combine chains to run in parallel
        parallel_chain = RunnableParallel(
            joke=joke_chain,
            poem=poem_chain
        )
        
        # Get results
        result = parallel_chain.invoke({"topic": topic})
        
        return f"""
Joke: {result['joke'].content}

Poem: {result['poem'].content}
"""
        
    except Exception as e:
        return f"Error: {str(e)}"

# Create Gradio interface
demo = gr.Interface(
    fn=process_parallel,
    inputs=[
        gr.Textbox(label="Topic", placeholder="Enter a topic..."),
        gr.Textbox(label="OpenAI API Key", type="password")
    ],
    outputs=gr.Textbox(label="Results", lines=6),
    title="LangChain Parallel Processing Demo",
    description="Generates a joke and poem about your topic simultaneously"
)

if __name__ == "__main__":
    demo.launch()