How to use the aioitertools.builtins.next function in aioitertools

Example:

        data = ["A", "a", "b", "c", "C", "c"]

        async for key, group in groupby(data, key=str.lower):
            key  # "a", "b", "c"
            group  # ["A", "a"], ["b"], ["c", "C", "c"]

    """
    if key is None:
        key = lambda x: x

    grouping: List[T] = []

    it = iter(itr)
    item = await next(it)
    grouping = [item]

    j = await maybe_await(key(item))
    async for item in it:
        k = await maybe_await(key(item))
        if k != j:
            yield j, grouping
            grouping = [item]
        else:
            grouping.append(item)
        j = k

    yield j, grouping

Accepts both a standard function or a coroutine for accumulation.

    Example:

        data = [1, 2, 3, 4]

        async def mul(a, b):
            return a * b

        async for total in accumulate(data, func=mul):
            ...  # 1, 2, 6, 24

    """
    itr = iter(itr)
    try:
        total: T = await next(itr)
    except AnyStop:
        return

    yield total
    async for item in itr:
        total = await maybe_await(func(total, item))
        yield total