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

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Text this: Transformation optics and hidden symmetries