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GNU GENERAL PUBLIC LICENSE
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Copyright (C) 1989, 1991 Free Software Foundation, Inc.
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675 Mass Ave, Cambridge, MA 02139, USA
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Everyone is permitted to copy and distribute verbatim copies
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of this license document, but changing it is not allowed.
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The licenses for most software are designed to take away your
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freedom to share and change it. By contrast, the GNU General Public
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License is intended to guarantee your freedom to share and change free
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software--to make sure the software is free for all its users. This
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General Public License applies to most of the Free Software
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Foundation's software and to any other program whose authors commit to
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using it. (Some other Free Software Foundation software is covered by
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the GNU Library General Public License instead.) You can apply it to
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When we speak of free software, we are referring to freedom, not
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price. Our General Public Licenses are designed to make sure that you
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have the freedom to distribute copies of free software (and charge for
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this service if you wish), that you receive source code or can get it
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if you want it, that you can change the software or use pieces of it
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in new free programs; and that you know you can do these things.
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To protect your rights, we need to make restrictions that forbid
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anyone to deny you these rights or to ask you to surrender the rights.
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These restrictions translate to certain responsibilities for you if you
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distribute copies of the software, or if you modify it.
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For example, if you distribute copies of such a program, whether
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gratis or for a fee, you must give the recipients all the rights that
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you have. You must make sure that they, too, receive or can get the
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source code. And you must show them these terms so they know their
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We protect your rights with two steps: (1) copyright the software, and
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(2) offer you this license which gives you legal permission to copy,
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distribute and/or modify the software.
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Also, for each author's protection and ours, we want to make certain
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that everyone understands that there is no warranty for this free
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software. If the software is modified by someone else and passed on, we
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want its recipients to know that what they have is not the original, so
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that any problems introduced by others will not reflect on the original
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Finally, any free program is threatened constantly by software
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patents. We wish to avoid the danger that redistributors of a free
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program will individually obtain patent licenses, in effect making the
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program proprietary. To prevent this, we have made it clear that any
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patent must be licensed for everyone's free use or not licensed at all.
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The precise terms and conditions for copying, distribution and
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GNU GENERAL PUBLIC LICENSE
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TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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0. This License applies to any program or other work which contains
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a notice placed by the copyright holder saying it may be distributed
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under the terms of this General Public License. The "Program", below,
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refers to any such program or work, and a "work based on the Program"
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means either the Program or any derivative work under copyright law:
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that is to say, a work containing the Program or a portion of it,
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either verbatim or with modifications and/or translated into another
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language. (Hereinafter, translation is included without limitation in
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the term "modification".) Each licensee is addressed as "you".
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Activities other than copying, distribution and modification are not
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covered by this License; they are outside its scope. The act of
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running the Program is not restricted, and the output from the Program
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is covered only if its contents constitute a work based on the
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Program (independent of having been made by running the Program).
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Whether that is true depends on what the Program does.
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1. You may copy and distribute verbatim copies of the Program's
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source code as you receive it, in any medium, provided that you
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conspicuously and appropriately publish on each copy an appropriate
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copyright notice and disclaimer of warranty; keep intact all the
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notices that refer to this License and to the absence of any warranty;
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and give any other recipients of the Program a copy of this License
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along with the Program.
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You may charge a fee for the physical act of transferring a copy, and
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you may at your option offer warranty protection in exchange for a fee.
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2. You may modify your copy or copies of the Program or any portion
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of it, thus forming a work based on the Program, and copy and
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distribute such modifications or work under the terms of Section 1
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above, provided that you also meet all of these conditions:
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a) You must cause the modified files to carry prominent notices
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stating that you changed the files and the date of any change.
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b) You must cause any work that you distribute or publish, that in
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whole or in part contains or is derived from the Program or any
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part thereof, to be licensed as a whole at no charge to all third
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parties under the terms of this License.
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c) If the modified program normally reads commands interactively
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when run, you must cause it, when started running for such
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interactive use in the most ordinary way, to print or display an
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announcement including an appropriate copyright notice and a
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notice that there is no warranty (or else, saying that you provide
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a warranty) and that users may redistribute the program under
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these conditions, and telling the user how to view a copy of this
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License. (Exception: if the Program itself is interactive but
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does not normally print such an announcement, your work based on
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the Program is not required to print an announcement.)
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These requirements apply to the modified work as a whole. If
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identifiable sections of that work are not derived from the Program,
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and can be reasonably considered independent and separate works in
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themselves, then this License, and its terms, do not apply to those
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sections when you distribute them as separate works. But when you
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distribute the same sections as part of a whole which is a work based
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on the Program, the distribution of the whole must be on the terms of
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this License, whose permissions for other licensees extend to the
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entire whole, and thus to each and every part regardless of who wrote it.
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Thus, it is not the intent of this section to claim rights or contest
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your rights to work written entirely by you; rather, the intent is to
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exercise the right to control the distribution of derivative or
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collective works based on the Program.
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In addition, mere aggregation of another work not based on the Program
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with the Program (or with a work based on the Program) on a volume of
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a storage or distribution medium does not bring the other work under
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the scope of this License.
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3. You may copy and distribute the Program (or a work based on it,
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under Section 2) in object code or executable form under the terms of
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Sections 1 and 2 above provided that you also do one of the following:
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a) Accompany it with the complete corresponding machine-readable
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source code, which must be distributed under the terms of Sections
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1 and 2 above on a medium customarily used for software interchange; or,
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b) Accompany it with a written offer, valid for at least three
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years, to give any third party, for a charge no more than your
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cost of physically performing source distribution, a complete
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machine-readable copy of the corresponding source code, to be
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distributed under the terms of Sections 1 and 2 above on a medium
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customarily used for software interchange; or,
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c) Accompany it with the information you received as to the offer
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to distribute corresponding source code. (This alternative is
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allowed only for noncommercial distribution and only if you
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received the program in object code or executable form with such
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an offer, in accord with Subsection b above.)
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The source code for a work means the preferred form of the work for
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making modifications to it. For an executable work, complete source
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code means all the source code for all modules it contains, plus any
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associated interface definition files, plus the scripts used to
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control compilation and installation of the executable. However, as a
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special exception, the source code distributed need not include
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anything that is normally distributed (in either source or binary
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form) with the major components (compiler, kernel, and so on) of the
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operating system on which the executable runs, unless that component
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itself accompanies the executable.
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If distribution of executable or object code is made by offering
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access to copy from a designated place, then offering equivalent
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access to copy the source code from the same place counts as
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distribution of the source code, even though third parties are not
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compelled to copy the source along with the object code.
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4. You may not copy, modify, sublicense, or distribute the Program
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except as expressly provided under this License. Any attempt
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otherwise to copy, modify, sublicense or distribute the Program is
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void, and will automatically terminate your rights under this License.
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However, parties who have received copies, or rights, from you under
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this License will not have their licenses terminated so long as such
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parties remain in full compliance.
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5. You are not required to accept this License, since you have not
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signed it. However, nothing else grants you permission to modify or
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distribute the Program or its derivative works. These actions are
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prohibited by law if you do not accept this License. Therefore, by
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modifying or distributing the Program (or any work based on the
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Program), you indicate your acceptance of this License to do so, and
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all its terms and conditions for copying, distributing or modifying
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the Program or works based on it.
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6. Each time you redistribute the Program (or any work based on the
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Program), the recipient automatically receives a license from the
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original licensor to copy, distribute or modify the Program subject to
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these terms and conditions. You may not impose any further
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restrictions on the recipients' exercise of the rights granted herein.
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You are not responsible for enforcing compliance by third parties to
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7. If, as a consequence of a court judgment or allegation of patent
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infringement or for any other reason (not limited to patent issues),
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conditions are imposed on you (whether by court order, agreement or
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otherwise) that contradict the conditions of this License, they do not
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excuse you from the conditions of this License. If you cannot
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distribute so as to satisfy simultaneously your obligations under this
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License and any other pertinent obligations, then as a consequence you
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may not distribute the Program at all. For example, if a patent
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license would not permit royalty-free redistribution of the Program by
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all those who receive copies directly or indirectly through you, then
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the only way you could satisfy both it and this License would be to
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refrain entirely from distribution of the Program.
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If any portion of this section is held invalid or unenforceable under
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any particular circumstance, the balance of the section is intended to
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apply and the section as a whole is intended to apply in other
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It is not the purpose of this section to induce you to infringe any
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patents or other property right claims or to contest validity of any
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such claims; this section has the sole purpose of protecting the
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integrity of the free software distribution system, which is
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implemented by public license practices. Many people have made
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generous contributions to the wide range of software distributed
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through that system in reliance on consistent application of that
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system; it is up to the author/donor to decide if he or she is willing
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to distribute software through any other system and a licensee cannot
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This section is intended to make thoroughly clear what is believed to
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be a consequence of the rest of this License.
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8. If the distribution and/or use of the Program is restricted in
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certain countries either by patents or by copyrighted interfaces, the
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original copyright holder who places the Program under this License
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may add an explicit geographical distribution limitation excluding
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those countries, so that distribution is permitted only in or among
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countries not thus excluded. In such case, this License incorporates
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the limitation as if written in the body of this License.
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9. The Free Software Foundation may publish revised and/or new versions
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of the General Public License from time to time. Such new versions will
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be similar in spirit to the present version, but may differ in detail to
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address new problems or concerns.
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Each version is given a distinguishing version number. If the Program
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specifies a version number of this License which applies to it and "any
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later version", you have the option of following the terms and conditions
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either of that version or of any later version published by the Free
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Software Foundation. If the Program does not specify a version number of
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this License, you may choose any version ever published by the Free Software
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10. If you wish to incorporate parts of the Program into other free
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programs whose distribution conditions are different, write to the author
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to ask for permission. For software which is copyrighted by the Free
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Software Foundation, write to the Free Software Foundation; we sometimes
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make exceptions for this. Our decision will be guided by the two goals
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of preserving the free status of all derivatives of our free software and
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of promoting the sharing and reuse of software generally.
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11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
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FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
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OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
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PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
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OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
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TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
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PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
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REPAIR OR CORRECTION.
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12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
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WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
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REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
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INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
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OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
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TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
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YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
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PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGES.
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END OF TERMS AND CONDITIONS