LICENSE

Copyright (c) 2019 Kailai Xu

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.


                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 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
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  The licenses for most software and other practical works are designed
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  When we speak of free software, we are referring to freedom, not
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                       TERMS AND CONDITIONS

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  9. Acceptance Not Required for Having Copies.

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  10. Automatic Licensing of Downstream Recipients.

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  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
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  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
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  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
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  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
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                     END OF TERMS AND CONDITIONS