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    Pythonlangchain-coreCallbacks

    Callbacks

    Classes

    Class

    BaseCallbackHandler

    Base callback handler.

    Class

    AsyncCallbackHandler

    Base async callback handler.

    Class

    BaseCallbackManager

    Base callback manager.

    Class

    CallbackManager

    Callback manager for LangChain.

    Class

    AsyncCallbackManager

    Async callback manager that handles callbacks from LangChain.

    Class

    UsageMetadataCallbackHandler

    Callback Handler that tracks AIMessage.usage_metadata.

    Functions

    Function

    get_usage_metadata_callback

    Get usage metadata callback.