PreambleThe GNU General Public License is a free, copyleft license for softwareand other kinds of works.The licenses for most software and other practical works are designedto take away your freedom to share and change the works. By contrast,the GNU General Public License is intended to guarantee your freedomto share and change all versions of a program--to make sure it remainsfree software for all its users. We, the Free Software Foundation, use theGNU General Public License for most of our software; it applies also toany other work released this way by its authors. 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