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

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Text this: Identification for difference in differences with cross-section and panel data