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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def nwise(iterable, n):
 r""" Sliding window iterator. Iterator that acts like a sliding window of size `n`; slides over some iterable `n` items at a time. If iterable has `m` elements, this function will return an iterator over `m-n+1` tuples. Parameters iterable : iterable An iterable object. n : int Window size. Returns ------- iterator of tuples. Iterator of size `n` tuples Notes ----- First `n` iterators are created:: iters = tee(iterable, n) Next, iterator `i` is advanced `i` times:: for i, it in enumerate(iters):
 for _ in range(i):
 next(it, None) Finally, the iterators are zipped back up again:: return zip(*iters) Examples -------- [(2, 5, 7), (5, 7, 4), (7, 4, 2), (4, 2, 8), (2, 8, 6)] [(2, 5), (5, 7), (7, 4), (4, 2), (2, 8), (8, 6)] [(2,), (5,), (7,), (4,), (2,), (8,), (6,)] [(2, 5, 7, 4, 2, 8, 6)] .. todo:: [] [] A sliding window of size `n` over a list of `m` elements gives `m-n+1` windows True True True """

    iters = tee(iterable, n)
    for i, it in enumerate(iters):
        for _ in range(i):
            next(it, None)
    return zip(*iters)