examples/techniques/ollama_langchain.py

from langchain_core.prompts import ChatPromptTemplate
from langchain_ollama.llms import OllamaLLM

template = """Question: {question}

Answer: Let's think step by step."""

prompt = ChatPromptTemplate.from_template(template)

model = OllamaLLM(model="llama3.2:1b-instruct-q4_K_M")

chain = prompt | model

res = chain.invoke({"question": "What is LangChain?"})

print(res)