Class Task

dask/_task_spec.py:636–838

class Task(GraphNode):
    func: Callable
    args: tuple
    kwargs: dict
    _data_producer: bool
    _token: str | None
    _is_coro: bool | None
    _repr: str | None

    __slots__ = tuple(__annotations__)

    def __init__(
        self,
        key: Any,
        func: Callable,
        /,
        *args: Any,
        _data_producer: bool = False,
        **kwargs: Any,
    ):
        self.key = key
        self.func = func
        if isinstance(func, Task):
            raise TypeError("Cannot nest tasks")

        self.args = args
        self.kwargs = kwargs
        _dependencies: set[KeyType] | None = None
        for a in itertools.chain(args, kwargs.values()):
            if isinstance(a, TaskRef):
                if _dependencies is None:
                    _dependencies = {a.key}
                else:
                    _dependencies.add(a.key)
            elif isinstance(a, GraphNode) and a.dependencies:
                if _dependencies is None:
                    _dependencies = set(a.dependencies)
                else:
                    _dependencies.update(a.dependencies)
        if _dependencies:
            self._dependencies = frozenset(_dependencies)
        else:
            self._dependencies = _no_deps
        self._is_coro = None
        self._token = None
        self._repr = None
        self._data_producer = _data_producer

    @property
    def data_producer(self) -> bool:
        return self._data_producer

    def has_subgraph(self) -> bool:
        return self.func == _execute_subgraph

    def copy(self):
        return type(self)(
            self.key,