Ubuntu 16.04 (AWS EC2) 上的 python 依赖关系被破坏

Question

我试图删除 Ubuntu 16.04 上所有已安装的 python。就目前情况而言，我现在明白我不应该这样做。但是，仅仅尝试重新安装 python 是行不通的。

当我尝试时

$ sudo apt install -f --reinstall python3
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Suggested packages:
  python3-doc python3-tk python3-venv
The following NEW packages will be installed:
  python3
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
4 not fully installed or removed.
Need to get 0 B/8,710 B of archives.
After this operation, 68.6 kB of additional disk space will be used.
Setting up python3.5-minimal (3.5.2-2ubuntu0~16.04.5) ...
# Empty sitecustomize.py to avoid a dangling symlink
Could not find platform independent libraries <prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encodings'

Current thread 0x00007fc6b52dd700 (most recent call first):
Aborted
dpkg: error processing package python3.5-minimal (--configure):
 subprocess installed post-installation script returned error exit status 134
dpkg: dependency problems prevent configuration of python3-minimal:
 python3-minimal depends on python3.5-minimal (>= 3.5.1-2~); however:
  Package python3.5-minimal is not configured yet.

dpkg: error processing package python3-minimal (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 python3.5-minimal
 python3-minimal
E: Sub-process /usr/bin/dpkg returned an error code (1)

$ python3
Could not find platform independent libraries <prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encodings'

Current thread 0x00007f87215c4700 (most recent call first):
Aborted

我尝试安装一些依赖项，但发现缺少但无济于事

$ sudo apt-get -f install python3.5-minimal
Reading package lists... Done
Building dependency tree       
Reading state information... Done
python3.5-minimal is already the newest version (3.5.2-2ubuntu0~16.04.5).
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 dh-python : Depends: python3:any (>= 3.3.2-2~)
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

尝试过不同的事情，但此时我不知道如何解决这个问题

$ sudo apt-get -f install dh-python
Reading package lists... Done
Building dependency tree       
Reading state information... Done
dh-python is already the newest version (2.20151103ubuntu1.1).
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 dh-python : Depends: python3:any (>= 3.3.2-2~)
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

Answer 1

ubuntu 从 16 升级到 18 后，我在 python3 上遇到了类似的问题。但是你可以尝试在 16 上使用我的解决方案。只需使用 apt-getagainstapt

注意：我需要在我的系统中安装 python2.7。

我按照这些步骤操作：

1. 卸载所有 python3 软件包：

   sudo apt remove python3 && sudo apt autoremove

2. 但这对我没有帮助。因此将尝试定义系统中仍然存在哪些包：

   apt list --installed | grep python*

   //possible output:
   WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
   libpython-stdlib/bionic,now 2.7.15~rc1-1 amd64 [installed,automatic]
   libpython2.7-minimal/bionic-updates,bionic-security,now 2.7.17-1~18.04ubuntu1.2 amd64 [installed,automatic]
   libpython2.7-stdlib/bionic-updates,bionic-security,now 2.7.17-1~18.04ubuntu1.2 amd64 [installed,automatic]
   libpython3-stdlib/bionic-updates,now 3.6.7-1~18.04 amd64 [installed]
   libpython3.5/now 3.5.2-2ubuntu0~16.04.12 amd64 [installed,local]
   libpython3.5-minimal/now 3.5.2-2ubuntu0~16.04.12 amd64 [installed,local]
   libpython3.5-stdlib/now 3.5.2-2ubuntu0~16.04.12 amd64 [installed,local]
   libpython3.6/bionic-updates,bionic-security,now 3.6.9-1~18.04ubuntu1.3 amd64 [installed,automatic]
   libpython3.6-minimal/bionic-updates,bionic-security,now 3.6.9-1~18.04ubuntu1.3 amd64 [installed,automatic]
   libpython3.6-stdlib/bionic-updates,bionic-security,now 3.6.9-1~18.04ubuntu1.3 amd64 [installed,automatic]
   python/bionic,now 2.7.15~rc1-1 amd64 [installed]
   python-apt-common/bionic-updates,bionic-updates,bionic-security,bionic-security,now 1.6.5ubuntu0.5 all [installed]
   python-minimal/bionic,now 2.7.15~rc1-1 amd64 [installed,automatic]
   python2.7/bionic-updates,bionic-security,now 2.7.17-1~18.04ubuntu1.2 amd64 [installed,automatic]
   python2.7-minimal/bionic-updates,bionic-security,now 2.7.17-1~18.04ubuntu1.2 amd64 [installed,automatic]
   

3. 我们可以看到，系统中存在一些python3包。将删除它们。

   sudo apt remove libpython3-stdlib libpython3.5 libpython3.5-minimal libpython3.5-stdlib libpython3.6 libpython3.6-minimal libpython3.6-stdlib

4. 现在，尝试安装 python3

   sudo apt install python3

5. 一切应该没问题