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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 reduce_vertex(self, name1, *names):
 same Vertex instance as name1 """

        v = self.vertices[name1]
        for n in names:
            w = self.vertices[n]
            v.alias.update(w.alias)
            # replace mapping from n w by to v
            self.vertices[n] = v