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GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
Preamble
The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General
Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for
all its users. This General Public License applies to most of the Free Software Foundation's software and to any other program
whose authors commit to using it. (Some other Free Software Foundation software is covered by the GNU Lesser General
Public License instead.) You can apply it to your programs, too.
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 to surrender the
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 give the recipients all the rights
that you have. 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 FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be
distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a
"work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work
containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language.
(Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you".
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act
of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work
based on the Program (independent of having been made by running the Program). Whether that is true depends on what the
Program does.
1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that
you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep
intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program
a copy of this License along with the Program.
You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in
exchange for a fee.
2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and
copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these
conditions:
