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           __   __   __   _      ___    __    __  
  ____     \ \\/ // | || | ||   / _ \\  \ \\ / // 
 |    \\    \ ` //  | '--' ||  / //\ \\  \ \/ //  
 | [] ||     | ||   | .--. || |  ___  ||  \  //   
 |  __//     |_||   |_|| |_|| |_||  |_||   \//    
 |_|`-`      `-`'   `-`  `-`  `-`   `-`     `     
 `-`

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Text this: Symmetry Groups Associated With Tilings on a Flat Torus