我正在使用 Debian Jessie。当我尝试安装 gedit 时遇到以下问题：
XXX@XXX:~$ sudo apt-get install gedit
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
gedit : Depends: python3-gi-cairo (>= 3.0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
请注意，我在尝试安装其他软件包时遇到类似的问题，不仅仅是 Gedit。
我的 source.list 文件：
# deb cdrom:[Debian GNU/Linux 8.2.0 _Jessie_ - Official amd64 lxde-CD Binary-1 20150906-11:10]/ jessie main
#deb cdrom:[Debian GNU/Linux 8.2.0 _Jessie_ - Official amd64 lxde-CD Binary-1 20150906-11:10]/ jessie main
deb http://ftp.fr.debian.org/debian/ jessie main contrib non free
deb-src http://ftp.fr.debian.org/debian/ jessie main
deb http://security.debian.org/ jessie/updates main
deb-src http://security.debian.org/ jessie/updates main
# jessie-updates, previously known as 'volatile'
deb http://ftp.fr.debian.org/debian/ jessie-updates main
deb-src http://ftp.fr.debian.org/debian/ jessie-updates main
#deb http://ftp.fr.debian.org/debian/ jessie main contrib non-free
# testing
#deb http://ftp.fr.debian.org/debian testing main contrib non-free
#deb http://ftp.fr.debian.org/debian testing main
deb http://httpredir.debian.org/debian jessie-backports main contrib non-free
目录sources.list.d 是空的。
编辑 ：
我试过 ：
XXX@XXX:~$ sudo apt-get -f install
[sudo] password for XXX:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
ca-certificates-java default-jre default-jre-headless firebird2.5-common
firebird2.5-common-doc firebird2.5-server-common fonts-opensymbol
java-common libabw-0.1-1 libatk-wrapper-java libatk-wrapper-java-jni
libboost-date-time1.58.0 libboost-filesystem1.55.0 libboost-system1.55.0
libclucene-contribs1v5 libclucene-core1v5 libcmis-0.5-5v5 libe-book-0.1-1
libeot0 libetonyek-0.1-1 libexttextcat-2.0-0 libexttextcat-data libfbclient2
libfbembed2.5 libglew1.10 libgltf-0.0-0v5 liblangtag-common liblangtag1
libmhash2 libmwaw-0.3-3 libmythes-1.2-0 libodfgen-0.1-1 libraptor2-0
librasqal3 librdf0 libsctp1 libwps-0.4-4 libyajl2 lksctp-tools openjdk-7-jre
openjdk-7-jre-headless tzdata-java uno-libs3 ure
Use 'sudo apt autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
然后尝试再次安装，但收到相同的错误消息。
编辑2：
XXX@XXX~$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
openssl
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.