在OSX上运行pip会出现以下错误:
Traceback (most recent call last):
File "/usr/local/bin/pip", line 9, in <module>
load_entry_point('pip==6.0.6', 'console_scripts', 'pip')()
File "build/bdist.macosx-10.10-x86_64/egg/pkg_resources/__init__.py", line 519, in load_entry_point
File "build/bdist.macosx-10.10-x86_64/egg/pkg_resources/__init__.py", line 2630, in load_entry_point
File "build/bdist.macosx-10.10-x86_64/egg/pkg_resources/__init__.py", line 2310, in load
File "build/bdist.macosx-10.10-x86_64/egg/pkg_resources/__init__.py", line 2316, in resolve
File "/usr/local/Cellar/python/2.7.7_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-6.0.6-py2.7.egg/pip/__init__.py", line 15, in <module>
from pip.vcs import git, mercurial, subversion, bazaar # noqa
File "/usr/local/Cellar/python/2.7.7_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-6.0.6-py2.7.egg/pip/vcs/mercurial.py", line 11, in <module>
from pip.download import path_to_url
File "/usr/local/Cellar/python/2.7.7_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-6.0.6-py2.7.egg/pip/download.py", line 36, in <module>
from pip._vendor.cachecontrol import CacheControlAdapter
File "/usr/local/Cellar/python/2.7.7_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-6.0.6-py2.7.egg/pip/_vendor/__init__.py", line 81, in load_module
raise ImportError("No module named '%s'" % (name,))
ImportError: No module named 'pip._vendor.cachecontrol'
知道我做错了什么吗？
并非特定于 OSX，但对于现在处理此问题的人来说，Python 3.8.0 位于最稳定的存储库上，这可能是因为您在更新包时出于兼容性原因保留了某个包，或者删除了所需的包。
就我而言，我删除了该msgpack软件包并计划重新安装它以解决另一个问题，但删除该软件包后，我无法通过 pip 重新安装它。
解决方案是（重新）安装python-msgpack.
即 Arch 的默认包管理器：
sudo pacman -Sy python-msgpack