def prod_demand_rule(m, j):
    expr = 0
    for l in [ll for (ll, jj) in con_pool_prod if (jj == j)]:
        expr += m.y[(l, j)]
    for i in [ii for (ii, jj) in con_feed_prod if (jj == j)]:
        expr += m.z[(i, j)]
    return (min_demand[j], expr, max_demand[j])
def prod_demand_rule(m, j):
    expr = 0
    for l in [ll for (ll, jj) in con_pool_prod if (jj == j)]:
        expr += m.y[(l, j)]
    for i in [ii for (ii, jj) in con_feed_prod if (jj == j)]:
        expr += m.z[(i, j)]
    return (min_demand[j], expr, max_demand[j])