点坏了；已安装 v9.0.1，但需要 setuptools 8.1.1答案

【问题标题】：pip broken; v9.0.1 installed but setuptools required 8.1.1点坏了；已安装 v9.0.1，但需要 setuptools 8.1.1
【发布时间】：2017-11-03 01:15:30
【问题描述】：

过去没有任何问题或最近进行了任何更改，但截至今天早上，使用 pip 做任何事情，包括只运行不带参数的“pip”都会导致异常说 setuptools 需要 8.1.1 但是9.0.1 已安装 - 所以我无法升级 setuptools 或降级 pip。

$ pip
Traceback (most recent call last):
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 659, in _build_master
    ws.require(__requires__)
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 967, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 858, in resolve
    raise VersionConflict(dist, req).with_context(dependent_req)
pkg_resources.VersionConflict: (pip 9.0.1 (/usr/local/lib/python3.5/site-packages), Requirement.parse('pip==8.1.1'))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/mobiglas/bin/pip", line 5, in <module>
    from pkg_resources import load_entry_point
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 3017, in <module>
    @_call_aside
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 3003, in _call_aside
    f(*args, **kwargs)
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 3030, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 661, in _build_master
    return cls._build_from_requirements(__requires__)
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 674, in _build_from_requirements
    dists = ws.resolve(reqs, Environment())
  File "/usr/local/lib/python3.5/site-packages/pkg_resources/__init__.py", line 853, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'pip==8.1.1' distribution was not found and is required by the application

【问题讨论】：

试试 get_pip.py :install_pip

标签： python pip setuptools

【解决方案1】：

解决方法是使用easy_install重新安装pip

$ easy_install-3.5 pip 
Searching for pip
Best match: pip 9.0.1
Adding pip 9.0.1 to easy-install.pth file
Installing pip3 script to /home/.../bin
Installing pip3.5 script to /home/.../bin
Installing pip script to /home/.../bin

Using /usr/local/lib/python3.5/site-packages
Processing dependencies for pip
Finished processing dependencies for pip

【讨论】：