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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 down_alpha_beta(returns, factor_returns, **kwargs):
 """ Computes alpha and beta for periods when the benchmark return is negative. Parameters see documentation for `alpha_beta`. Returns ------- alpha : float beta : float """

    return down(returns, factor_returns, function=alpha_beta_aligned, **kwargs)