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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_joint_sfs_folded(s, n1, n2):
 """Scale a folded joint site frequency spectrum. Parameters s : array_like, int, shape (m_chromosomes//2, n_chromosomes//2) Folded joint site frequency spectrum. n1, n2 : int, optional The total number of chromosomes called in each population. Returns ------- joint_sfs_folded_scaled : ndarray, int, shape (m_chromosomes//2, n_chromosomes//2) Scaled folded joint site frequency spectrum. """
  # noqa
    out = np.empty_like(s)
    for i in range(s.shape[0]):
        for j in range(s.shape[1]):
            out[i, j] = s[i, j] * i * j * (n1 - i) * (n2 - j)
    return out