app.py

from langchain_community.chat_models import ChatOllama
from langchain_core.output_parsers import StrOutputParser
from langchain_core.prompts import ChatPromptTemplate

# Local Llama3
llm = ChatOllama(
    model="llama3",
    keep_alive=-1,
    temperature=0,
    max_new_tokens=512)

# you can changed template for genereted your text
prompt = ChatPromptTemplate.from_template("Write me a 100 word article on {topic} from the perspective of a {profession}. ")

chain = prompt | llm | StrOutputParser()

for chunk in chain.stream({"topic": "LLMs", "profession": "labor"}):
    print(chunk, end="", flush=True)