GNU GENERAL PUBLIC LICENSE Version 3, 29 June 2007 Copyright (C) 2007 Free Software Foundation, Inc. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Preamble The GNU General Public License is a free, copyleft license for software and other kinds of works. The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things. To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you not to exercise these rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it. For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on the same freedoms to the recipients that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights. We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute, and/or modify the software. Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations. Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone's free use or not licensed at all. The precise terms and conditions for copying, distribution, and modification follow. TERMS AND CONDITIONS 0. Definitions. This License refers to version 3 of the GNU General Public License. "Copyright" also means copyright-like laws that apply to other kinds of works, such as semiconductor mask works. "The Program" refers to any copyrightable work licensed under this License. Each licensee is addressed as "you". "You" means the individual or entity exercising the permissions granted by this License. "Your" has a corresponding meaning. "License" means this document. "Copyright notice" means a copyright notice as used in the program. "Source code" means the preferred form of the work for making modifications to it. "Object code" means any non-source form of a work. "Contribution" means any work of authorship, including the original version of the work and any modifications or additions to that work, that is submitted to the Licensor by the Contributor. "Contributors" are the people who contribute code or documentation to the project. "Substitute" means an original work or an equivalent work produced using the Program, in whole or in part. "Modified version" means a work based on the Program or any part of it. "Propagation" means the inclusion of the work in a product or distribution. "Redistribution" means any form of distribution including the making available of copies or derivative works. "Proprietary software" means software that is not free software. 1. Source Code. The source code for a work is the preferred form of the work for making modifications to it. 2. Basic Permissions. You are granted the rights to copy, distribute, and/or modify the work, subject to the conditions in this License. 3. Copyleft. You must keep the GPL notice and a copy of this License with any copies or modified versions of the work. You must also provide access to the source code. 4. Conveying Modified Source Versions. You may convey modified versions of the work, provided you keep the GPL notice and include a copy of this License. You must also include a prominent notice stating that you have modified the work. 5. Conveying Non-Source Forms. You may convey non-source forms of the work, provided you provide access to the source code and include a copy of this License. 6. Additional Terms. You may not impose any further restrictions on the rights granted by this License. 7. No Warranty. The work is provided "as-is" without any warranty. The authors are not liable for any damages. 8. Termination. If you violate the terms of this License, the license is terminated automatically. 9. Acceptance. By copying, distributing, or modifying the work, you accept the terms of this License. 10. GNU General Public License. This License is intended to protect the rights of users and authors and is designed to ensure that software remains free. For more details and the complete text, you can refer to the official [GNU GPL v3 License](https://www.gnu.org/licenses/gpl-3.0.html). S