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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 scale_sfs_folded(s, n):
 """Scale a folded site frequency spectrum. Parameters s : array_like, int, shape (n_chromosomes//2,) Folded site frequency spectrum. n : int Number of chromosomes called. Returns ------- sfs_folded_scaled : ndarray, int, shape (n_chromosomes//2,) Scaled folded site frequency spectrum. """

    k = np.arange(s.shape[0])
    out = s * k * (n - k) / n
    return out