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    LangGraph Checkpoint
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    Store Postgres
    Checkpoint SQLite
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    Pythonlanggraphpregel_algoprepare_single_task
    Function●Since v0.6

    prepare_single_task

    Copy
    prepare_single_task(
      task_path: tuple[Any, ...],
      task_id_checksum: str
    View source on GitHub
    |
    None
    ,
    *
    ,
    checkpoint
    :
    Checkpoint
    ,
    checkpoint_id_bytes
    :
    bytes
    ,
    checkpoint_null_version
    :
    V
    |
    None
    ,
    pending_writes
    :
    list
    [
    PendingWrite
    ]
    ,
    processes
    :
    Mapping
    [
    str
    ,
    PregelNode
    ]
    ,
    channels
    :
    Mapping
    [
    str
    ,
    BaseChannel
    ]
    ,
    managed
    :
    ManagedValueMapping
    ,
    config
    :
    RunnableConfig
    ,
    step
    :
    int
    ,
    stop
    :
    int
    ,
    for_execution
    :
    bool
    ,
    store
    :
    BaseStore
    |
    None
    =
    None
    ,
    checkpointer
    :
    BaseCheckpointSaver
    |
    None
    =
    None
    ,
    manager
    :
    None
    |
    ParentRunManager
    |
    AsyncParentRunManager
    =
    None
    ,
    input_cache
    :
    dict
    [
    INPUT_CACHE_KEY_TYPE
    ,
    Any
    ]
    |
    None
    =
    None
    ,
    cache_policy
    :
    CachePolicy
    |
    None
    =
    None
    ,
    retry_policy
    :
    Sequence
    [
    RetryPolicy
    ]
    =
    (
    )
    )
    ->
    None
    |
    PregelTask
    |
    PregelExecutableTask

    Prepares a single task for the next Pregel step, given a task path, which uniquely identifies a PUSH or PULL task within the graph.