def METHOD_NAME(self, vec3):
    if vec3 is None:
        return
    self.x = vec3.X()
    self.y = vec3.Y()
    self.z = vec3.Z()
    self.test1 = vec3.Test1()
    self.test2 = vec3.Test2()
    if vec3.Test3() is not None:
        self.test3 = MyGame.Example.NestedUnion.Test.TestT.InitFromObj(vec3.Test3())