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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 central_vertices(self):
 """Vertices that have the lowest maximum distance to any other vertex"""

        max_distances = self.distances.max(0)
        max_distances_min = max_distances[max_distances > 0].min()
        return (max_distances == max_distances_min).nonzero()[0]