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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 _merge_cluster(self, c2keep, c2empty):
 r""" Little helper function to merger clusters but only add the uninvaded elements """

        while len(self.queue[c2empty]) > 0:
            temp = [_pc, _id, _type] = hq.heappop(self.queue[c2empty])
            if self[_type+'.invasion_sequence'][_id] == -1:
                hq.heappush(self.queue[c2keep], temp)
        self.invasion_running[c2empty] = False