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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 sfs_folded_scaled(ac, n=None):
 """Compute the folded site frequency spectrum scaled such that a constant value is expected across the spectrum for neutral variation and constant population size. Parameters ac : array_like, int, shape (n_variants, 2) Allele counts array. n : int, optional The total number of chromosomes called. Returns ------- sfs_folded_scaled : ndarray, int, shape (n_chromosomes//2,) An array where the value of the kth element is the number of variants with minor allele count k, multiplied by the scaling factor (k * (n - k) / n). """


    # check input
    ac, n = _check_ac_n(ac, n)

    # compute the site frequency spectrum
    s = sfs_folded(ac, n=n)

    # apply scaling
    s = scale_sfs_folded(s, n)

    return s