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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 _pack_bits_into_byte(iterable):
 """\ Packs eight bits into one byte. If the length of the iterable is not a multiple of eight, ``0x0`` is used to fill-up the missing values. """

    return (reduce(lambda x, y: (x << 1) + y, e)
            for e in zip_longest(*[iter(iterable)] * 8, fillvalue=0x0))