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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 fold_sfs(s, n):
 """Fold a site frequency spectrum. Parameters s : array_like, int, shape (n_chromosomes,) Site frequency spectrum n : int Total number of chromosomes called. Returns ------- sfs_folded : ndarray, int Folded site frequency spectrum """


    # check inputs
    s = asarray_ndim(s, 1)
    assert s.shape[0] <= n + 1, 'invalid number of chromosomes'

    # need to check s has all entries up to n
    if s.shape[0] < n + 1:
        sn = np.zeros(n + 1, dtype=s.dtype)
        sn[:s.shape[0]] = s
        s = sn

    # fold
    nf = (n + 1) // 2
    n = nf * 2
    o = s[:nf] + s[nf:n][::-1]

    return o