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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 index_natsorted(seq, key=lambda x: x, number_type=float, signed=True, exp=True):
 """\ Sorts a sequence naturally, but returns a list of sorted the indeces and not the sorted list. [2, 0, 1] ['num2', 'num3', 'num5'] ['baz', 'foo', 'bar'] [2, 0, 1] """

    from operator import itemgetter
    item1 = itemgetter(1)
    # Pair the index and sequence together, then sort by
    index_seq_pair = [[x, key(y)] for x, y in zip(range(len(seq)), seq)]
    index_seq_pair.sort(key=lambda x: natsort_key(item1(x),
                                                  number_type=number_type,
                                                  signed=signed, exp=exp))
    return [x[0] for x in index_seq_pair]