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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 unpack_default(iterable, length=3, default=None):
 """ Unpacks given iterable maintaining given length and filling missing entries with given default. :param iterable: iterable. :type iterable: object :param length: Iterable length. :type length: int :param default: Filling default object. :type default: object :return: Unpacked iterable. :rtype: object """


    return itertools.islice(itertools.chain(iter(iterable), itertools.repeat(default)), length)