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

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Text this: Maximal and minimal congruences on some semigroups