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

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Text this: Space-time nonseparable pulses : constructing isodiffracting donut pulses from plane waves and single-cycle pulses