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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 flatten(iterable):
 """Flatten an arbitrarily deep list"""

    # likely not used
    iterable = iter(iterable)
    while True:
        try:
            item = next(iterable)
        except StopIteration:
            break

        if isinstance(item, six.string_types):
            yield item
            continue

        try:
            data = iter(item)
            iterable = itertools.chain(data, iterable)
        except:
            yield item