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    Pythonlangchain-corecallbacksbaseBaseCallbackManagermerge
    Method●Since v0.2

    merge

    Merge the callback manager with another callback manager.

    May be overwritten in subclasses.

    Primarily used internally within merge_configs.

    Copy
    merge(
        self,
        other: BaseCallbackManager,
    ) -> Self

    Example:

    # Merging two callback managers`
    from langchain_core.callbacks.manager import (
        CallbackManager,
        trace_as_chain_group,
    )
    from langchain_core.callbacks.stdout import StdOutCallbackHandler
    
    manager = CallbackManager(handlers=[StdOutCallbackHandler()], tags=["tag2"])
    with trace_as_chain_group("My Group Name", tags=["tag1"]) as group_manager:
        merged_manager = group_manager.merge(manager)
        print(merged_manager.handlers)
        # [
        #    <langchain_core.callbacks.stdout.StdOutCallbackHandler object at ...>,
        #    <langchain_core.callbacks.streaming_stdout.StreamingStdOutCallbackHandler object at ...>,
        # ]
    
        print(merged_manager.tags)
        #    ['tag2', 'tag1']
    View source on GitHub