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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 do_static_merge(cls, c_source, c_target):
 """By the time we're just folding in clusters, there's no need to maintain self.INSTANCES and self.clusters, so we just call this method """

        c_target.extend(c_source)
        c_source.parent = c_target.parent
        cls.CLUSTERS.remove(c_source)
        for m in c_source.mentions:
            cls.MENTION_TO_CLUSTER[m] = c_target