app.py

import streamlit as st
from langchain_openai import ChatOpenAI
from langchain.schema import AIMessage, HumanMessage, SystemMessage
import os

# Set your OpenAI API key
os.environ["OPENAI_API_KEY"] = "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"  # Replace with your key

st.set_page_config(page_title="LangChain Demo", page_icon=":robot:")
st.header("Hey, I'm your Chat GPT")

if "sessionMessages" not in st.session_state:
    st.session_state.sessionMessages = [
        SystemMessage(content="You are a helpful assistant.")
    ]

def load_answer(question):
    st.session_state.sessionMessages.append(HumanMessage(content=question))
    assistant_answer = chat.invoke(st.session_state.sessionMessages)
    st.session_state.sessionMessages.append(AIMessage(content=assistant_answer.content))
    return assistant_answer.content

def get_text():
    return st.text_input("You: ")

# Initialize ChatOpenAI with recommended parameters
chat = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)

user_input = get_text()
submit = st.button('Generate')

if submit:
    response = load_answer(user_input)
    st.subheader("Answer:")
    st.write(response)