Describir: Gyotaku, fish print. What it is? How to make it?

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