import os
from langchain_groq import ChatGroq

def get_llm():
    """
    Returns the language model instance (LLM) using ChatGroq API.
    The LLM used is Llama 3.3 with a versatile 70 billion parameter model.
    """
    api_key = os.getenv("CHAT_GROQ_API_KEY")
    if not api_key:
        raise ValueError("Please set the CHAT_GROQ_API_KEY environment variable.")
    
    llm = ChatGroq(
        model="llama-3.3-70b-versatile",
        temperature=0,
        max_tokens=1024,
        api_key=api_key
    )
    return llm