[E017] Error: cannot declare magic method `EnumWithSleep::__sleep` in an enum
   ,-[code.php:4:21]
   |
 3 | enum EnumWithSleep {
   *      ^^^^^^^^^^^^^  
   *                      
 4 |     public function __sleep() {}
   *                     ^^^|^^^  
   *                        `----- try removing this magic method
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