使用14.04的pip问题

[sh42]

各位好，我是python新手。我在我机器上安装了pip和python，python好像安装了好几个版本，有3.6.1和3.4，我运行pip的时候弹出这个东西，不知道什么意思，请各位指点。谢谢！

luhang@hive:~$ pip --version
Traceback (most recent call last):
File "/usr/local/bin/pip", line 6, in <module>
from pkg_resources import load_entry_point
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3036, in <module>
@_call_aside
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3020, in _call_aside
f(*args, **kwargs)
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3049, in _initialize_master_working_set
working_set = WorkingSet._build_master()
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 654, in _build_master
ws.require(__requires__)
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 968, in require
needed = self.resolve(parse_requirements(requirements))
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 854, in resolve
raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'pip==1.5.4' distribution was not found and is required by the application

[sh42]

在线等。追加个问题，怎么设置默认的python版本呢，我看我系统里稀里糊涂装了python2.7.6 python3.6.1和python3.4，pip和python版本怎么对应起来。

[astolia]

先把你装的都删掉。再用系统源里自带的
sudo apt-get install --reinstall python3.4 python3-pip

[astolia]

不要改默认版本，你要用python2.7.x的就运行python2.7，python3.4的就运行python3.4。
.py里的shebang也写成 #!/usr/bin/python2.7这样带上版本号

[sh42]

不要改默认版本，你要用python2.7.x的就运行python2.7，python3.4的就运行python3.4。
.py里的shebang也写成 #!/usr/bin/python2.7这样带上版本号

感谢回复。按照您的说法，pip -v没有问题了，但是运行其他程序还是有问题：
luhang@hive:~$ jupyter notebook
Traceback (most recent call last):
File "/usr/local/bin/jupyter", line 6, in <module>
from pkg_resources import load_entry_point
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3036, in <module>
@_call_aside
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3020, in _call_aside
f(*args, **kwargs)
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 3049, in _initialize_master_working_set
working_set = WorkingSet._build_master()
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 654, in _build_master
ws.require(__requires__)
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 968, in require
needed = self.resolve(parse_requirements(requirements))
File "/usr/local/lib/python3.4/dist-packages/pkg_resources/__init__.py", line 854, in resolve
raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'decorator' distribution was not found and is required by traitlets

我打印了一下which python3和which python：
luhang@hive:~$ which python
/usr/bin/python
luhang@hive:~$ which python3
/usr/local/bin/python3
发现python3默认的是python3.6，在/usr/local/bin/python3这个link。而python3.4是在/usr/bin/python3这个link，我直觉感觉，是不是把默认的python3改成指向3.4就行了。别的程序还要用3.6我就没删除