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

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Text this: Linear Operators that Preserve the Edgesum of a Graph