Ubuntu16.04安裝Python3.6及安裝過程中錯誤解決

Ubuntu16.04默認安裝了Python2.7和3.5

請注意，系統自帶的python千萬不能卸載！

輸入命令python

按Ctrl+D退出python命令行

輸入命令sudo add-apt-repository ppa:jonathonf/python-3.6

Reading package lists... Done
E: Problem executing scripts APT::Update::Post-Invoke-Success
'if /usr/bin/test -w /var/cache/app-info -a -e /usr/bin/appstreamcli;
 then appstreamcli refresh > /dev/null;
 fi'
E: Sub-process returned an error code

在運行sudo apt-get update時出現如上信息，解決方法如下：

sudo pkill -KILL appstreamcli

wget -P /tmp https://launchpad.net/ubuntu/+archive/primary/+files/appstream_0.9.4-1ubuntu1_amd64.deb https://launchpad.net/ubuntu/+archive/primary/+files/libappstream3_0.9.4-1ubuntu1_amd64.deb

sudo dpkg -i /tmp/appstream_0.9.4-1ubuntu1_amd64.deb /tmp/libappstream3_0.9.4-1ubuntu1_amd64.deb

執行完上述命令之後再次運行sudo apt-get update就不會再出現上面的錯誤。

按Enter確認

輸入命令sudo apt-get update

輸入命令sudo apt-get install python3.6

按Y確認

 

調整Python3的優先級，使得3.6優先級較高

sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.5 1

sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 2

更改默認值，python默認爲Python2，現在修改爲Python3

sudo update-alternatives --install /usr/bin/python python /usr/bin/python2 100

sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 150

 

此時再輸入命令python

可以看到此時已經是Python3.6了