I have had the same problem when I used easy-install to install pip for python 2.7.14. For me the solution was (might not be the best, but worked for me, and this is probably the simplest) that the folder that contained the easy-install.py also contained a folder pkg_resources, and i have copy-pasted this folder into the same folder where my pip-script.py script was (python27\Scripts). Since then, I found it in the python27\Lib\site-packages\pip-9.0.1-py2.7.egg\pip\_vendor folder as well, it might be a better solution to modify the pip-script.py file to import this.

在尝试了几个这样的答案后，然后联系了一位同事，在Ubuntu 16.04上对我有效的是:

pip install --force-reinstall -U setuptools
pip install --force-reinstall -U pip

在我的情况下，只有旧版本的枕头3.1.1有问题(枕头4。X工作正常)，现在解决了!

您可以使用该命令 Sudo apt-get install—重新安装python3-pkg-resources 如果您正在使用python3，那么我就是这种情况。

我之前有这个错误，最高评级的答案给了我一个错误，试图下载ez_setup.py文件。我找到了另一个来源，所以你可以运行命令:

curl http://peak.telecommunity.com/dist/ez_setup.py | python

我发现我还必须使用sudo来让它工作，所以你可能需要运行:

sudo curl http://peak.telecommunity.com/dist/ez_setup.py | sudo python

我还创建了另一个可以下载脚本的位置:

https://gist.github.com/ajtrichards/42e73562a89edb1039f3

看起来他们已经离开bitbucket，现在在github (https://github.com/pypa/setuptools)

执行的命令为:

wget https://bootstrap.pypa.io/ez_setup.py -O - | sudo python

在windows上，我安装了从www.lfd.uci.edu/~gohlke/pythonlibs/下载的pip，然后遇到了这个问题。

所以我应该先安装setuptools(easy_install)。