from langchain_google_genai import ChatGoogleGenerativeAI from dotenv import load_dotenv import os load_dotenv() google_api_key = os.getenv("GEMINI_API_KEY") model ="gemini-2.5-flash-lite" def run_hello_langchain(): """ Instantiates a ChatGoogleGenerativeAI model. Invokes it with a simple prompt. Prints the model's response. """ llm = ChatGoogleGenerativeAI(model=model, google_api_key=google_api_key) response = llm.invoke("explain RLHF in 2 lines!") print(response.content) run_hello_langchain()