app.py

import os
from dotenv import find_dotenv, load_dotenv
import openai
from langchain.chat_models import ChatOpenAI
from langchain.llms import OpenAI
from langchain.prompts import PromptTemplate
from langchain.chains import LLMChain, SequentialChain
import streamlit as st 



load_dotenv(find_dotenv())

#==== Using OpenAI Chat API =======
llm_model = "gpt-3.5-turbo"

# chat = ChatOpenAI(temperature=0.9, model=llm_model)
open_ai = OpenAI(temperature=0.7)


def generate_lullaby(location, name, language):

    template = """ 
        As a children's book writer, please come up with a simple and short (90 words)
        lullaby based on the location
        {location}
        and the main character {name}
        
        STORY:
    """

    prompt = PromptTemplate(input_variables=["location", "name"],
                            template=template)

    chain_story = LLMChain(llm=open_ai, prompt=prompt, 
                        output_key="story",
                        verbose=True)


    # ======= Sequential Chain =====
    # chain to translate the story to Portuguese
    template_update = """
    Translate the {story} into {language}.  Make sure 
    the language is simple and fun.

    TRANSLATION:
    """

    prompt_translate = PromptTemplate(input_variables=["story", "language"],
                                    template=template_update)

    chain_translate = LLMChain(
        llm=open_ai,
        prompt=prompt_translate,
        output_key="translated"
    )


    # ==== Create the Sequential Chain ===
    overall_chain = SequentialChain(
        chains=[chain_story, chain_translate],
        input_variables=["location", "name", "language"],
        output_variables=["story", "translated"], # return story and the translated variables!
        verbose=True
    )

    response = overall_chain({"location": location, 
                            "name": name,
                            "language": language
                            })



    return response


def main():
    st.set_page_config(page_title="Generate Children's Lullaby",
                       layout="centered")
    st.title("Let AI Write and Translate a Lullaby for You 📖")
    st.header("Get Started...")

    location_input = st.text_input(label="Where is the story set?")
    main_character_input = st.text_input(label="What's the main charater's name")
    language_input = st.text_input(label="Translate the story into...")

    submit_button = st.button("Submit")
    if location_input and main_character_input and language_input:
        if submit_button:
            with st.spinner("Generating lullaby..."):
                response = generate_lullaby(location=location_input,
                                            name= main_character_input,
                                            language=language_input)

                with st.expander("English Version"):
                    st.write(response['story'])
                with st.expander(f"{language_input} Version"):
                    st.write(response['translated'])

            st.success("Lullaby Successfully Generated!")























 #Invoking main function
if __name__ == '__main__':
    main()