def _execute_task(arg, cache, dsk=None):
    if isinstance(arg, list):
        return [_execute_task(a, cache) for a in arg]
    elif istask(arg):
        func, args = arg[0], arg[1:]
        args2 = [_execute_task(a, cache) for a in args]
        return func(*args2)
    elif not ishashable(arg):
        return arg
    elif arg in cache:
        return cache[arg]
    else:
        return arg
Validate that the value from destination header is
dataset/ETHPy150Open dask/dask/dask/async.py/_execute_task--crossover with--dataset/ETHPy150Open openstack/swift/swift/common/constraints.py/check_destination_header