 the probability that it
    appears late in the permutation.

    >>> data = "abcdefgh"
    >>> weights = range(1, len(data) + 1)
    >>> sample(data, k=len(data), weights=weights)  # doctest: +SKIP
    ['c', 'a', 'b', 'e', 'g', 'd', 'h', 'f']
    r