public function license(): string
    {
        $key        = mb_strtoupper($this->c::uuidV4());
        return $key = implode('-', str_split($key, 8));
    }
public function license(): string
    {
        $key        = mb_strtoupper($this->c::uuidV4());
        return $key = implode('-', str_split($key, 8));
    }
public function license ( ) : string { $ key = mb_strtoupper ( $ this -> c :: uuidV4 ( ) ) ; return $ key = implode ( '-' , str_split ( $ key , 8 ) ) ; }
License key.

@since 170824.30708 Key generator.

@return string UUID w/ 4 dashed parts (35 uppercase bytes).

@example `CAF0F02F-DFC248C7-B4EF607C-F85C154A`
License key .