Ubuntu16.04上将系统自带的python3.5升级到3.6
安装aioredis时提示Python版本需>=3.5.3，所以进行升级
命令如下：
$ sudo add-apt-repository ppa:jonathonf/python-3.6 $ sudo apt-get update $ sudo apt-get install python3.6*
注意，安装python3.6的时候一定要加*，将3.6所需的依赖库也一起装上
注意，python3.5不要卸载，卸载会损坏系统。
# 移除原3.4link $ sudo rm /usr/bin/python3 # 更换默认python3 的版本为3.6 $ sudo ln -s /usr/bin/python3.6 /usr/bin/python3
安装完Python后pip需重新安装：
$ wget https://bootstrap.pypa.io/get-pip.py --no-check-certificate $ sudo python get-pip.py
问题解决
参考：https://askubuntu.com/questions/1037528/apt-get-upgrade-error-for-python-packages-in-ubuntu-16-04
在ubuntu上将python3.5升级到python3.6，执行如下命令时，遇到错误：
sudo apt-get install python3.6*
Building dependency tree
Reading state information... Done
Note, selecting 'python3.6-2to3' for glob 'python3.6*'
Note, selecting 'python3.6-venv' for glob 'python3.6*'
Note, selecting 'python3.6-examples' for glob 'python3.6*'
Note, selecting 'python3.6' for glob 'python3.6*'
Note, selecting 'python3.6-tk' for glob 'python3.6*'
Note, selecting 'python3.6-lib2to3' for glob 'python3.6*'
Note, selecting 'python3.6-minimal' for glob 'python3.6*'
Note, selecting 'python3.6-gdbm' for glob 'python3.6*'
Note, selecting 'python3.6-dbg' for glob 'python3.6*'
Note, selecting 'python3.6-dev' for glob 'python3.6*'
Note, selecting 'python3.6-doc' for glob 'python3.6*'
Note, selecting 'python3.6-distutils' for glob 'python3.6*'
Note, selecting 'python3-tk' instead of 'python3.6-tk'
Note, selecting 'python3-distutils' instead of 'python3.6-distutils'
Note, selecting 'python3-gdbm' instead of 'python3.6-gdbm'
Note, selecting 'python3-lib2to3' instead of 'python3.6-lib2to3'
python3-gdbm is already the newest version (3.6.5-3~16.04.york4).
python3-tk is already the newest version (3.6.5-3~16.04.york4).
python3.6 is already the newest version (3.6.8-1~16.04.york1).
python3.6-dbg is already the newest version (3.6.8-1~16.04.york1).
python3.6-dev is already the newest version (3.6.8-1~16.04.york1).
python3.6-doc is already the newest version (3.6.8-1~16.04.york1).
python3.6-examples is already the newest version (3.6.8-1~16.04.york1).
python3.6-minimal is already the newest version (3.6.8-1~16.04.york1).
python3.6-venv is already the newest version (3.6.8-1~16.04.york1).
The following NEW packages will be installed:
python3-distutils python3-lib2to3
0 upgraded, 2 newly installed, 0 to remove and 261 not upgraded.
Need to get 0 B/219 kB of archives.
After this operation, 1,090 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
(Reading database ... 292643 files and directories currently installed.)
Preparing to unpack .../python3-lib2to3_3.6.5-3~16.04.york0.2_all.deb ...
Unpacking python3-lib2to3 (3.6.5-3~16.04.york0.2) ...
dpkg: error processing archive /var/cache/apt/archives/python3-lib2to3_3.6.5-3~16.04.york0.2_all.deb (--unpack):
trying to overwrite '/usr/lib/python3.6/lib2to3/Grammar.txt', which is also in package libpython3.6-stdlib:amd64 3.6.8-1~16.04.york1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Preparing to unpack .../python3-distutils_3.6.5-3~16.04.york0.2_all.deb ...
Unpacking python3-distutils (3.6.5-3~16.04.york0.2) ...
dpkg: error processing archive /var/cache/apt/archives/python3-distutils_3.6.5-3~16.04.york0.2_all.deb (--unpack):
trying to overwrite '/usr/lib/python3.6/distutils/dir_util.py', which is also in package libpython3.6-stdlib:amd64 3.6.8-1~16.04.york1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Errors were encountered while processing:
/var/cache/apt/archives/python3-lib2to3_3.6.5-3~16.04.york0.2_all.deb
/var/cache/apt/archives/python3-distutils_3.6.5-3~16.04.york0.2_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
对于这种错误，我采取的处理方法是手动强行安装两个安装失败的包（黄底色红字部分）：
sudo dpkg --install --force all /var/cache/apt/archives/python3-lib2to3_3.6.5-3~16.04.york0.2_all.deb
sudo dpkg --install --force all /var/cache/apt/archives/python3-distutils_3.6.5-3~16.04.york0.2_all.deb
然后再执行
sudo apt-get install python3.6*
安装成功！