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

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Text this: Principles of the Spin model checker