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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 decrease_weight(self, proxy):
 """Decreasing the weight of a proxy by multiplying dec_ratio"""

        new_weight = proxy.weight * self.dec_ratio
        if new_weight < self.weight_thr:
            self.remove_proxy(proxy)
        else:
            proxy.weight = new_weight