Reference Guide

software (and charge for them 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 prevent others from
denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the
software, or if you modify it: responsibilities to respect the freedom of others. For example, if you distribute copies of such a program,
whether gratis or for a fee, you must pass on to the recipients the same freedoms 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. Developers that use the GNU GPL
protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy,
distribute and/or modify it. For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free
software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not
be attributed erroneously to authors of previous versions. Some devices are designed to deny users access to install or run modified
versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting
users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which
is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those
products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions
of the GPL, as needed to protect the freedom of users. Finally, every program is threatened constantly by software patents. States should
not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the
special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents
cannot be used to render the program non-free. The precise terms and conditions for copying, distribution and modification follow.
TERMS AND CONDITIONS
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 masks. “The Program” refers to any copyrightable work licensed under this License. Each licensee is
addressed as “you”. “Licensees” and “recipients” may be individuals or organizations. To “modify” a work means to copy from or adapt all
or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a
“modified version” of the earlier work or a work “based on” the earlier work. A “covered work” means either the unmodified Program or a
work based on the Program. To “propagate” a work means to do anything with it that, without permission, would make you directly or
secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy.
Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other
activities as well. To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere
interaction with a user through a computer network, with no transfer of a copy, is not conveying. An interactive user interface displays
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licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user
commands or options, such as a menu, a prominent item in the list meets this criterion.
1. Source Code.
The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-
source form of a work. A “Standard Interface” means an interface that either is an official standard defined by a recognized standards
body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working
in that language. The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in
the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use
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source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of
the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code
interpreter used to run it. The “Corresponding Source” for a work in object code form means all the source code needed to generate,
install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However,
it does not include the work's System Libraries, or general-purpose tools or generally available free programs which are used
unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface
definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms
that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms
and other parts of the work. The Corresponding Source need not include anything that users can regenerate automatically from other
parts of the Corresponding Source. The Corresponding Source for a work in source code form is that same work.
2. Basic Permissions.
All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated
conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a
covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges
your rights of fair use or other equivalent, as provided by copyright law. You may make, run and propagate covered works that you do
not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the
sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided
that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or
running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them
Third party licenses
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