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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 add_vertex(self, x, y, z, name):
 """add vertex by coordinate and uniq name x y z is coordinates of vertex name is uniq name to refer the vertex returns Vertex object whici is added. """

        self.vertices[name] = Vertex(x, y, z, name)
        return self.vertices[name]