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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 absolute_extreme_coefficient_ratio(model):
 """ Return the maximum and minimum absolute, non-zero coefficients. Parameters model : cobra.Model The metabolic model under investigation. """

    s_matrix, _, _ = con_helpers.stoichiometry_matrix(
        model.metabolites, model.reactions
    )
    abs_matrix = np.abs(s_matrix)
    return abs_matrix.max(), abs_matrix[abs_matrix > 0].min()