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             ___      _____      ___     _    _   
    ___     / _ \\   /  ___||   / _ \\  | |  | || 
   /   ||  / //\ \\ | // __    / //\ \\ | |/\| || 
  | [] || |  ___  ||| \\_\ || |  ___  |||  /\  || 
   \__ || |_||  |_|| \____//  |_||  |_|||_// \_|| 
    -|_|| `-`   `-`   `---`   `-`   `-` `-`   `-` 
     `-`

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Text this: On the diamond operator related to the wave equation