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    Pythonlangchain-coreoutput_parserstransform
    Module●Since v0.1

    transform

    Base classes for output parsers that can handle streaming input.

    Attributes

    attribute
    T

    Functions

    function
    run_in_executor

    Run a function in an executor.

    Classes

    class
    BaseMessage

    Base abstract message class.

    Messages are the inputs and outputs of a chat model.

    Examples include HumanMessage, AIMessage, and SystemMessage.

    class
    BaseMessageChunk

    Message chunk, which can be concatenated with other Message chunks.

    class
    BaseOutputParser

    Base class to parse the output of an LLM call.

    Output parsers help structure language model responses.

    class
    ChatGeneration

    A single chat generation output.

    A subclass of Generation that represents the response from a chat model that generates chat messages.

    The message attribute is a structured representation of the chat message. Most of the time, the message will be of type AIMessage.

    Users working with chat models will usually access information via either AIMessage (returned from runnable interfaces) or LLMResult (available via callbacks).

    class
    ChatGenerationChunk

    ChatGeneration chunk.

    ChatGeneration chunks can be concatenated with other ChatGeneration chunks.

    class
    Generation

    A single text generation output.

    Generation represents the response from an "old-fashioned" LLM (string-in, string-out) that generates regular text (not chat messages).

    This model is used internally by chat model and will eventually be mapped to a more general LLMResult object, and then projected into an AIMessage object.

    LangChain users working with chat models will usually access information via AIMessage (returned from runnable interfaces) or LLMResult (available via callbacks). Please refer to AIMessage and LLMResult for more information.

    class
    GenerationChunk

    GenerationChunk, which can be concatenated with other Generation chunks.

    class
    RunnableConfig

    Configuration for a Runnable.

    Note

    Custom values

    The TypedDict has total=False set intentionally to:

    • Allow partial configs to be created and merged together via merge_configs
    • Support config propagation from parent to child runnables via var_child_runnable_config (a ContextVar that automatically passes config down the call stack without explicit parameter passing), where configs are merged rather than replaced
    Example
    # Parent sets tags
    chain.invoke(input, config={"tags": ["parent"]})
    # Child automatically inherits and can add:
    # ensure_config({"tags": ["child"]}) -> {"tags": ["parent", "child"]}
    class
    BaseTransformOutputParser

    Base class for an output parser that can handle streaming input.

    class
    BaseCumulativeTransformOutputParser

    Base class for an output parser that can handle streaming input.

    View source on GitHub