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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 argmin(iterable, key=None, both=False):
 """See `argmax`. """

    if key is not None:
        it = imap(key, iterable)
    else:
        it = iter(iterable)
    score, argmin = reduce(min, izip(it, count()))
    if both:
        return argmin, score
    return argmin