def _pair_iter(it):
    it = iter(it)
    prev = next(it)
    for el in it:
        yield (prev, el)
        prev = el
    yield (prev, None)
| Creates a new taskgroup and attach it to the graph's root.
dataset/ETHPy150Open reefeed/wanish/wanish/tokenizers.py/_pair_iter--crossover with--dataset/ETHPy150Open mikrosimage/OpenRenderManagement/src/puliclient/__init__.py/Graph.addNewTaskGroup