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# How to stream LLM and Chat Model responses

LangChain provides streaming support for LLMs. Currently, we support streaming for the `OpenAI`, `ChatOpenAI`. and `Anthropic` implementations, but streaming support for other LLM implementations is on the roadmap. To utilize streaming, use a `CallbackHandler` that implements `on_llm_new_token`. In this example, we are using `StreamingStdOutCallbackHandler`.

    from langchain.llms import OpenAI, Anthropic
    from langchain.chat_models import ChatOpenAI
    from langchain.callbacks.base import CallbackManager
    from langchain.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
    from langchain.schema import HumanMessage

    llm = OpenAI(streaming=True, callback_manager=CallbackManager([StreamingStdOutCallbackHandler()]), verbose=True, temperature=0)
    resp = llm("Write me a song about sparkling water.")

    Verse 1
    I'm sippin' on sparkling water,
    It's so refreshing and light,
    It's the perfect way to quench my thirst
    On a hot summer night.

    Chorus
    Sparkling water, sparkling water,
    It's the best way to stay hydrated,
    It's so crisp and so clean,
    It's the perfect way to stay refreshed.

    Verse 2
    I'm sippin' on sparkling water,
    It's so bubbly and bright,
    It's the perfect way to cool me down
    On a hot summer night.

    Chorus
    Sparkling water, sparkling water,
    It's the best way to stay hydrated,
    It's so crisp and so clean,
    It's the perfect way to stay refreshed.

    Verse 3
    I'm sippin' on sparkling water,
    It's so light and so clear,
    It's the perfect way to keep me cool
    On a hot summer night.

    Chorus
    Sparkling water, sparkling water,
    It's the best way to stay hydrated,
    It's so crisp and so clean,
    It's the perfect way to stay refreshed.

We still have access to the end `LLMResult` if using `generate`. However, `token_usage` is not currently supported for streaming.

    llm.generate(["Tell me a joke."])

    Q: What did the fish say when it hit the wall?
    A: Dam!

    LLMResult(generations=[[Generation(text='\n\nQ: What did the fish say when it hit the wall?\nA: Dam!', generation_info={'finish_reason': None, 'logprobs': None})]], llm_output={'token_usage': {}, 'model_name': 'text-davinci-003'})

Here’s an example with the `ChatOpenAI` chat model implementation:

    chat = ChatOpenAI(streaming=True, callback_manager=CallbackManager([StreamingStdOutCallbackHandler()]), verbose=True, temperature=0)
    resp = chat([HumanMessage(content="Write me a song about sparkling water.")])

    Verse 1:
    Bubbles rising to the top
    A refreshing drink that never stops
    Clear and crisp, it's oh so pure
    Sparkling water, I can't ignore

    Chorus:
    Sparkling water, oh how you shine
    A taste so clean, it's simply divine
    You quench my thirst, you make me feel alive
    Sparkling water, you're my favorite vibe

    Verse 2:
    No sugar, no calories, just H2O
    A drink that's good for me, don't you know
    With lemon or lime, you're even better
    Sparkling water, you're my forever

    Chorus:
    Sparkling water, oh how you shine
    A taste so clean, it's simply divine
    You quench my thirst, you make me feel alive
    Sparkling water, you're my favorite vibe

    Bridge:
    You're my go-to drink, day or night
    You make me feel so light
    I'll never give you up, you're my true love
    Sparkling water, you're sent from above

    Chorus:
    Sparkling water, oh how you shine
    A taste so clean, it's simply divine
    You quench my thirst, you make me feel alive
    Sparkling water, you're my favorite vibe

    Outro:
    Sparkling water, you're the one for me
    I'll never let you go, can't you see
    You're my drink of choice, forevermore
    Sparkling water, I adore.

Here is an example with the `Anthropic` LLM implementation, which uses their `claude` model.

    llm = Anthropic(streaming=True, callback_manager=CallbackManager([StreamingStdOutCallbackHandler()]), verbose=True, temperature=0)
    llm("Write me a song about sparkling water.")

    Sparkling water, bubbles so bright,

    Fizzing and popping in the light.

    No sugar or calories, a healthy delight,

    Sparkling water, refreshing and light.

    Carbonation that tickles the tongue,

    In flavors of lemon and lime unsung.

    Sparkling water, a drink quite all right,

    Bubbles sparkling in the light.

    '\nSparkling water, bubbles so bright,\n\nFizzing and popping in the light.\n\nNo sugar or calories, a healthy delight,\n\nSparkling water, refreshing and light.\n\nCarbonation that tickles the tongue,\n\nIn flavors of lemon and lime unsung.\n\nSparkling water, a drink quite all right,\n\nBubbles sparkling in the light.'