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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 vertex(self, points):
 """ Given a set of points, return the closest vertex index to each point Parameters points : (n,3) float, list of points in space Returns distance : (n,) float, distance from source point to vertex vertex_id : (n,) int, index of mesh.vertices which is closest """

        tree = self._mesh.kdtree
        return tree.query(points)