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

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Text this: Best approximation in ℝ-trees