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LICENSE

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+# GNU Lesser General Public License
+
+_Version 3, 29 June 2007_  
+_Copyright © 2007 Free Software Foundation, Inc. &lt;<http://fsf.org/>&gt;_
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+
+This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+### 0. Additional Definitions
+
+As used herein, “this License” refers to version 3 of the GNU Lesser
+General Public License, and the “GNU GPL” refers to version 3 of the GNU
+General Public License.
+
+“The Library” refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+An “Application” is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+A “Combined Work” is a work produced by combining or linking an
+Application with the Library. The particular version of the Library
+with which the Combined Work was made is also called the “Linked
+Version”.
+
+The “Minimal Corresponding Source” for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+The “Corresponding Application Code” for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+### 1. Exception to Section 3 of the GNU GPL
+
+You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+### 2. Conveying Modified Versions
+
+If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+- **a)** under this License, provided that you make a good faith effort to
+  ensure that, in the event an Application does not supply the
+  function or data, the facility still operates, and performs
+  whatever part of its purpose remains meaningful, or
+
+- **b)** under the GNU GPL, with none of the additional permissions of
+  this License applicable to that copy.
+
+### 3. Object Code Incorporating Material from Library Header Files
+
+The object code form of an Application may incorporate material from
+a header file that is part of the Library. You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+- **a)** Give prominent notice with each copy of the object code that the
+  Library is used in it and that the Library and its use are
+  covered by this License.
+- **b)** Accompany the object code with a copy of the GNU GPL and this license
+  document.
+
+### 4. Combined Works
+
+You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+- **a)** Give prominent notice with each copy of the Combined Work that
+  the Library is used in it and that the Library and its use are
+  covered by this License.
+
+- **b)** Accompany the Combined Work with a copy of the GNU GPL and this license
+  document.
+
+- **c)** For a Combined Work that displays copyright notices during
+  execution, include the copyright notice for the Library among
+  these notices, as well as a reference directing the user to the
+  copies of the GNU GPL and this license document.
+
+- **d)** Do one of the following: - **0)** Convey the Minimal Corresponding Source under the terms of this
+  License, and the Corresponding Application Code in a form
+  suitable for, and under terms that permit, the user to
+  recombine or relink the Application with a modified version of
+  the Linked Version to produce a modified Combined Work, in the
+  manner specified by section 6 of the GNU GPL for conveying
+  Corresponding Source. - **1)** Use a suitable shared library mechanism for linking with the
+  Library. A suitable mechanism is one that **(a)** uses at run time
+  a copy of the Library already present on the user's computer
+  system, and **(b)** will operate properly with a modified version
+  of the Library that is interface-compatible with the Linked
+  Version.
+
+- **e)** Provide Installation Information, but only if you would otherwise
+  be required to provide such information under section 6 of the
+  GNU GPL, and only to the extent that such information is
+  necessary to install and execute a modified version of the
+  Combined Work produced by recombining or relinking the
+  Application with a modified version of the Linked Version. (If
+  you use option **4d0**, the Installation Information must accompany
+  the Minimal Corresponding Source and Corresponding Application
+  Code. If you use option **4d1**, you must provide the Installation
+  Information in the manner specified by section 6 of the GNU GPL
+  for conveying Corresponding Source.)
+
+### 5. Combined Libraries
+
+You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+- **a)** Accompany the combined library with a copy of the same work based
+  on the Library, uncombined with any other library facilities,
+  conveyed under the terms of this License.
+- **b)** Give prominent notice with the combined library that part of it
+  is a work based on the Library, and explaining where to find the
+  accompanying uncombined form of the same work.
+
+### 6. Revised Versions of the GNU Lesser General Public License
+
+The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License “or any later version”
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.