ubuntu14中下载了python3.6版本，pip3更新失败，之后导致apt-get也无法使用

具体报错如下：

zr@zr-OptiPlex-9020:~$ sudo pip3 install --upgrade pip
Traceback (most recent call last):
File “/usr/bin/pip3”, line 5, in
from pkg_resources import load_entry_point
File “/usr/lib/python3/dist-packages/pkg_resources.py”, line 1479, in
register_loader_type(importlib_bootstrap.SourceFileLoader, DefaultProvider)
AttributeError: module ‘importlib._bootstrap’ has no attribute ‘SourceFileLoader’
Error in sys.excepthook:
Traceback (most recent call last):
File “/usr/lib/python3/dist-packages/apport_python_hook.py”, line 63, in apport_excepthook
from apport.fileutils import likely_packaged, get_recent_crashes
File “/usr/lib/python3/dist-packages/apport/init.py”, line 5, in
from apport.report import Report
File “/usr/lib/python3/dist-packages/apport/report.py”, line 30, in
import apport.fileutils
File “/usr/lib/python3/dist-packages/apport/fileutils.py”, line 23, in
from apport.packaging_impl import impl as packaging
File “/usr/lib/python3/dist-packages/apport/packaging_impl.py”, line 20, in
import apt
File “/usr/lib/python3/dist-packages/apt/init.py”, line 23, in
import apt_pkg
ModuleNotFoundError: No module named ‘apt_pkg’

Original exception was:
Traceback (most recent call last):
File “/usr/bin/pip3”, line 5, in
from pkg_resources import load_entry_point
File “/usr/lib/python3/dist-packages/pkg_resources.py”, line 1479, in
register_loader_type(importlib_bootstrap.SourceFileLoader, DefaultProvider)
AttributeError: module ‘importlib._bootstrap’ has no attribute ‘SourceFileLoader’

这样的问题出现好几次了，我认为是由于python的版本问题造成的，我把版本切换回去还是报错，之后就apt-get也没法用了。有没有大神支招，我这到底是怎么了。