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  ______     ___    __    __    ______    ______  
 /_   _//   / _ \\  \ \\ / //  /_   _//  /_   _// 
   | ||    / //\ \\  \ \/ //    -| ||-   `-| |,-  
  _| ||   |  ___  ||  \  //     _| ||_     | ||   
 /__//    |_||  |_||   \//     /_____//    |_||   
 `--`     `-`   `-`     `      `-----`     `-`'

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發送短信 : Response function of four-dimensional topological insulator