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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 referenced_vertices(self):
 """ Which vertices in the current mesh are referenced by a face. Returns referenced : (len(self.vertices),) bool Which vertices are referenced by a face """

        referenced = np.zeros(len(self.vertices), dtype=np.bool)
        referenced[self.faces] = True
        return referenced