app.py

# Case Study 1 - Python AI Coder
# Building a Personal Python Programming Assistant using Streamlit and Groq API

# Import operating system utilities
import os

# Import Streamlit to build the web application interface
import streamlit as st
# Import the Groq client to interact with the language model API
from groq import Groq

# Configure Streamlit page settings
st.set_page_config(
    page_title="Python AI Coder",
    page_icon="🤖",
    layout="wide",
    initial_sidebar_state="expanded"
)

# Define the system prompt and assistant behaviour
CUSTOM_PROMPT = """
You are "Python AI Coder", an AI assistant specialised in Python programming.

Your mission is to help beginner developers understand programming concepts through clear explanations, practical examples, and official documentation references.

OPERATING RULES:

1. Programming Focus
Only answer questions related to programming, algorithms, data structures, libraries, frameworks, software engineering, and Python development.

If the user asks about unrelated subjects, politely explain that your purpose is to assist with programming topics only.

2. Response Structure

Always organise your answers using the following format:

- Clear Explanation
Provide a concise conceptual explanation of the topic.

- Code Example
Provide one or more complete Python examples using correct syntax and meaningful comments.

- Code Breakdown
Explain what each important section of the code does and why it is used.

- Documentation Reference
Finish with a section titled:

📚 Official Documentation

Include a relevant link to Python documentation or the official documentation of the library being discussed.

3. Communication Style

Use clear, professional, beginner-friendly language.

Avoid unnecessary jargon.

Focus on teaching and practical understanding.

4. Language Behaviour

Respond in the same language used by the user whenever possible.
"""

# Build the application sidebar
with st.sidebar:
    
    # Sidebar title
    st.title("🤖 Python AI Coder")
    
    # Brief description of the assistant
    st.markdown("An AI powered assistant focused on helping beginners learn Python programming.")
    
    # Groq API key input field
    groq_api_key = st.text_input(
        "Enter your Groq API Key", 
        type="password",
        help="Get your API key from https://console.groq.com/keys"
    )

    # Additional project information
    st.markdown("---")
    st.markdown("Built to help answer Python programming questions. AI may generate incorrect responses. Always validate the information provided.")

    st.markdown("---")
    st.markdown("This project was originally developed as part of a Data Science Academy learning programme. Learn more below:")

    # Link to Data Science Academy 
    st.markdown("🔗 [Data Science Academy](https://www.datascienceacademy.com.br)")
    
    # Support contact button
    st.link_button("✉️ Contact Data Science Academy Support", "mailto:suporte@datascienceacademy.com.br")

# Main application title
st.title("Python AI Coder")

# Secondary title
st.title("Personal Python Programming Assistant 🐍")

# Introductory description
st.caption("Ask your Python question and receive code examples, explanations, and official documentation references.")

# Initialise chat history if it does not exist
if "messages" not in st.session_state:
    st.session_state.messages = []

# Display previous conversation messages
for message in st.session_state.messages:
    with st.chat_message(message["role"]):
        st.markdown(message["content"])

# Initialise Groq client
client = None

# Check whether an API key has been provided
if groq_api_key:
    
    try:
        
        # Create Groq client instance
        client = Groq(api_key = groq_api_key)
    
    except Exception as e:
        
        # Display initialisation error
        st.sidebar.error(f"Error initialising Groq client: {e}")
        st.stop()

# Warn the user if messages exist but no API key has been provided
elif st.session_state.messages:
     st.warning("Please enter your Groq API key in the sidebar to continue.")

# Capture user input from the chat interface
if prompt := st.chat_input("What would you like to know about Python?"):
    
    # Prevent execution if no valid Groq client is available
    if not client:
        st.warning("Please enter your Groq API key in the sidebar to get started.")
        st.stop()

    # Store user message in session history
    st.session_state.messages.append({"role": "user", "content": prompt})
    
    # Display user message
    with st.chat_message("user"):
        st.markdown(prompt)

    # Prepare conversation history for API request
    messages_for_api = [{"role": "system", "content": CUSTOM_PROMPT}]
    for msg in st.session_state.messages:
        
        messages_for_api.append(msg)

    # Generate assistant response
    with st.chat_message("assistant"):
        
        with st.spinner("Analysing your question..."):
            
            try:
                
                # Request completion from the Groq API
                chat_completion = client.chat.completions.create(
                    messages = messages_for_api,
                    model = "openai/gpt-oss-20b", 
                    temperature = 0.7,
                    max_tokens = 2048,
                )
                
                # Extract generated response
                PcFaria_ai_resposta = chat_completion.choices[0].message.content
                
                # Display assistant response
                st.markdown(PcFaria_ai_resposta)
                
                # Save assistant response to session history
                st.session_state.messages.append({"role": "assistant", "content": PcFaria_ai_resposta})

            # Display API communication errors
            except Exception as e:
                st.error(f"An error occurred while communicating with the Groq API: {e}")

st.markdown(
    """
    <div style="text-align: center; color: gray;">
        <hr>
        <p>Python AI Coder - Originally developed as part of the Data Science Academy Python Fundamentals Programme and subsequently enhanced with additional features for learning and portfolio purposes.</p>
    </div>
    """,
    unsafe_allow_html=True
)

# End of application
# Developed and enhanced by Paulo Faria for learning and portfolio purposes