Copyright for deepin-image-viewer source package in Focal

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Upstream-Name: deepin-image-viewer
Source: https://github.com/linuxdeepin/deepin-image-viewer

Files: *
Copyright: 2016-2018 Deepin Technology Co., Ltd. 
License: GPL-3+

Files: qimage-plugins/libraw/*
Copyright: 2012 Alberto Mardegan 
License: GPL-3+

Files: debian/*
Copyright: 2016-2017 Deepin Technology Co., Ltd. 
           2017 Yangfl 
           2018 Boyuan Yang <073plan@gmail.com>
License: GPL-3+

License: GPL-3+
 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 package 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.
 .
 You should have received a copy of the GNU General Public License
 along with this program. If not, see .
 .
 On Debian systems, the complete text of the GNU General
 Public License version 3 can be found in "/usr/share/common-licenses/GPL-3".