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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(ac, n=None):
 """Compute the folded site frequency spectrum given reference and alternate allele counts at a set of biallelic variants. Parameters ac : array_like, int, shape (n_variants, 2) Allele counts array. n : int, optional The total number of chromosomes called. Returns ------- sfs_folded : ndarray, int, shape (n_chromosomes//2,) Array where the kth element is the number of variant sites with a minor allele count of k. """


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

    # compute minor allele counts
    mac = np.amin(ac, axis=1)

    # need platform integer for bincount
    mac = mac.astype(int, copy=False)

    # compute folded site frequency spectrum
    x = n//2 + 1
    s = np.bincount(mac, minlength=x)

    return s