python 利用pip安装包总是失败，原因是什么？

试一下先升级pip到最新版再操作。

输入代码：

Downloading Scrapy-1.1.1-py2.py3-none-any.whl (295kB): 295kB downloaded
Cleaning up...

Exception:

Traceback (most recent call last):

File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
status = self.run(options, args)

File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 278, in run
requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)

File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1260, in prepare_files
)[0]

IndexError: list index out of range

Storing debug log for failure in /home/jwwplus/.pip/pip.log