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1GNU GENERAL PUBLIC LICENSE2Version 3, 29 June 20074Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>5Everyone is permitted to copy and distribute verbatim copies6of this license document, but changing it is not allowed.8Preamble10The GNU General Public License is a free, copyleft license for11software and other kinds of works.13The licenses for most software and other practical works are designed14to take away your freedom to share and change the works. By contrast,15the GNU General Public License is intended to guarantee your freedom to16share and change all versions of a program--to make sure it remains free17software for all its users. We, the Free Software Foundation, use the18GNU General Public License for most of our software; it applies also to19any other work released this way by its authors. You can apply it to20your programs, too.22When we speak of free software, we are referring to freedom, not23price. 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