我有一台虚拟机：操作系统：Ubuntu 16.04.1 LTS 内核：Linux 4.4.0-59-generic 架构：x86-64
本系统中，python 有两个版本：2.7.12 和 3.5。还安装了 Pip。Pip 版本为：
pip 9.0.1 from /usr/local/lib/python2.7/dist-packages (python 2.7)
每次pip install <package>运行时都会出错。主要错误是因为lsb_release -a返回了错误。我lsb_release -a从控制台运行，然后出现无效语法错误：
File "/usr/bin/lsb_release", line 64
print("No LSB modules are available.", file=sys.stderr)
^
lsb_release文件的头部有以下内容：
#!/usr/bin/python3 -Es
但是系统似乎不知道如何到达 python3，尽管使用以下命令将 python3 的符号链接设置为 python3.5：
sudo ln -s /usr/bin/python3.5 /usr/bin/python3
命令的输出ls -l /usr/bin/python*如下：
lrwxrwxrwx 1 root root 9 Dec 9 2015 /usr/bin/python -> python2.7
lrwxrwxrwx 1 root root 9 Dec 9 2015 /usr/bin/python2 -> python2.7
-rwxr-xr-x 1 root root 3546104 Nov 19 01:35 /usr/bin/python2.7
lrwxrwxrwx 1 root root 33 Nov 19 01:35 /usr/bin/python2.7-config -> x86_64-linux-gnu-python2.7-config
lrwxrwxrwx 1 root root 16 Dec 9 2015 /usr/bin/python2-config -> python2.7-config
lrwxrwxrwx 1 root root 9 Jan 26 09:07 /usr/bin/python3 -> python3.5
-rwxr-xr-x 2 root root 3546104 Jan 19 14:23 /usr/bin/python3.5
lrwxrwxrwx 1 root root 33 Nov 17 11:23 /usr/bin/python3.5-config -> x86_64-linux-gnu-python3.5-config
-rwxr-xr-x 2 root root 3546104 Jan 19 14:23 /usr/bin/python3.5m
lrwxrwxrwx 1 root root 34 Nov 17 11:23 /usr/bin/python3.5m-config -> x86_64-linux-gnu-python3.5m-config
lrwxrwxrwx 1 root root 16 Mar 23 2016 /usr/bin/python3-config -> python3.5-config
lrwxrwxrwx 1 root root 10 Jun 6 2016 /usr/bin/python3m -> python3.5m
lrwxrwxrwx 1 root root 17 Mar 23 2016 /usr/bin/python3m-config -> python3.5m-config
lrwxrwxrwx 1 root root 16 Dec 9 2015 /usr/bin/python-config -> python2.7-config
检查的版本python3.5，我得到了 2.7 版本：
$ /usr/bin/python3.5 --version
Python 2.7.12
当我执行时，系统显示有些不对劲
ll -a /usr/share/man/man1 | grep python。输出为：
-rw-r--r-- 1 root root 3367 Dec 9 2015 dh_python2.1.gz
-rw-r--r-- 1 root root 3280 May 18 2016 dh_python3.1.gz
lrwxrwxrwx 1 root root 14 Dec 9 2015 python.1.gz -> python2.7.1.gz
lrwxrwxrwx 1 root root 14 Dec 9 2015 python2.1.gz -> python2.7.1.gz
-rw-r--r-- 1 root root 5640 Nov 19 01:32 python2.7.1.gz
lrwxrwxrwx 1 root root 38 Nov 19 01:35 python2.7-config.1.gz -> x86_64-linux-gnu-python2.7-config.1.gz
lrwxrwxrwx 1 root root 21 Dec 9 2015 python2-config.1.gz -> python2.7-config.1.gz
lrwxrwxrwx 1 root root 14 Jun 6 2016 python3.1.gz -> python3.5.1.gz
-rw-r--r-- 1 root root 5174 Nov 17 10:43 python3.5.1.gz
lrwxrwxrwx 1 root root 38 Nov 17 11:23 python3.5-config.1.gz -> x86_64-linux-gnu-python3.5-config.1.gz
lrwxrwxrwx 1 root root 14 Nov 17 11:23 python3.5m.1.gz -> python3.5.1.gz
lrwxrwxrwx 1 root root 39 Nov 17 11:23 python3.5m-config.1.gz -> x86_64-linux-gnu-python3.5m-config.1.gz
lrwxrwxrwx 1 root root 21 Mar 23 2016 python3-config.1.gz -> python3.5-config.1.gz
lrwxrwxrwx 1 root root 15 Jun 6 2016 python3m.1.gz -> python3.5m.1.gz
lrwxrwxrwx 1 root root 22 Mar 23 2016 python3m-config.1.gz -> python3.5m-config.1.gz
lrwxrwxrwx 1 root root 21 Dec 9 2015 python-config.1.gz -> python2.7-config.1.gz
-rw-r--r-- 1 root root 921 Nov 19 00:15 x86_64-linux-gnu-python2.7-config.1.gz
lrwxrwxrwx 1 root root 39 Nov 17 11:23 x86_64-linux-gnu-python3.5-config.1.gz -> x86_64-linux-gnu-python3.5m-config.1.gz
-rw-r--r-- 1 root root 907 Nov 23 2013 x86_64-linux-gnu-python3.5m-config.1.gz
lrwxrwxrwx 1 root root 38 Mar 23 2016 x86_64-linux-gnu-python3-config.1.gz -> x86_64-linux-gnu-python3.5-config.1.gz
lrwxrwxrwx 1 root root 39 Mar 23 2016 x86_64-linux-gnu-python3m-config.1.gz -> x86_64-linux-gnu-python3.5m-config.1.gz
lrwxrwxrwx 1 root root 38 Dec 9 2015 x86_64-linux-gnu-python-config.1.gz -> x86_64-linux-gnu-python2.7-config.1.gz
3.5 软件包x86_64-linux-gnu-python3.5-config.1.gz有一个指向 3.5m 的符号链接。这很奇怪吗？
现在的问题是如何将 python3 指向正确的版本。有办法吗？
谢谢
答案1
您只需清除 lsb-release 包并再次安装即可解决您的问题。
$ sudo apt purge lsb-release
$ sudo apt install lsb-release
答案2
问题是 Python 版本 2.7.12 和 3.5.2 在虚拟机上出现了问题。一个快速的解决方案就是清除虚拟机并创建另一个。这解决了我的问题。